Fixes W293

14 files changed, 134 insertions, 134 deletions

diff --git a/pint/context.py b/pint/context.py
index 0034925..1ceb359 100644
--- a/pint/context.py
+++ b/pint/context.py
@@ -36,15 +36,15 @@ class Context:
     """A specialized container that defines transformation functions from one
     dimension to another. Each Dimension are specified using a UnitsContainer.
     Simple transformation are given with a function taking a single parameter.
-    
+
 
     Conversion functions may take optional keyword arguments and the context
     can have default values for these arguments.
-    
-    
+
+
     Additionally, a context may host redefinitions:
-    
-    
+
+
     A redefinition must be performed among units that already exist in the registry. It
     cannot change the dimensionality of a unit. The symbol and aliases are automatically
     inherited from the registry.
@@ -108,7 +108,7 @@ class Context:
         """Creates a new context that shares the funcs dictionary with the
         original context. The default values are copied from the original
         context and updated with the new defaults.
-        
+
         If defaults is empty, return the same context.
 
         Parameters
@@ -116,7 +116,7 @@ class Context:
         context : Context
             Original context.
         **defaults
-            
+
 
         Returns
         -------
@@ -298,7 +298,7 @@ class ContextChain(ChainMap):
     def insert_contexts(self, *contexts):
         """Insert one or more contexts in reversed order the chained map.
         (A rule in last context will take precedence)
-        
+
         To facilitate the identification of the context with the matching rule,
         the *relation_to_context* dictionary of the context is used.
         """
diff --git a/pint/definitions.py b/pint/definitions.py
index 947a189..16dd840 100644
--- a/pint/definitions.py
+++ b/pint/definitions.py
@@ -59,7 +59,7 @@ class Definition:
         Parameters
         ----------
         definition :
-            
+
 
         Returns
         -------
diff --git a/pint/formatting.py b/pint/formatting.py
index 4bcdf0b..0e84f82 100644
--- a/pint/formatting.py
+++ b/pint/formatting.py
@@ -18,7 +18,7 @@ __JOIN_REG_EXP = re.compile(r"\{\d*\}")
 
 def _join(fmt, iterable):
     """Join an iterable with the format specified in fmt.
-    
+
     The format can be specified in two ways:
     - PEP3101 format with two replacement fields (eg. '{} * {}')
     - The concatenating string (eg. ' * ')
@@ -26,9 +26,9 @@ def _join(fmt, iterable):
     Parameters
     ----------
     fmt : str
-        
+
     iterable :
-        
+
 
     Returns
     -------
diff --git a/pint/numpy_func.py b/pint/numpy_func.py
index ed91df1..0dcb878 100644
--- a/pint/numpy_func.py
+++ b/pint/numpy_func.py
@@ -23,13 +23,13 @@ HANDLED_FUNCTIONS = {}
 
 def _is_quantity(obj):
     """Test for _units and _magnitude attrs.
-    
+
     This is done in place of isinstance(Quantity, arg), which would cause a circular import.
 
     Parameters
     ----------
     obj : Object
-        
+
 
     Returns
     -------
@@ -44,7 +44,7 @@ def _is_quantity_sequence(obj):
     Parameters
     ----------
     obj : object
-        
+
 
     Returns
     -------
@@ -71,7 +71,7 @@ def _get_first_input_units(args, kwargs=None):
 
 def convert_arg(arg, pre_calc_units):
     """Convert quantities and sequences of quantities to pre_calc_units and strip units.
-    
+
     Helper function for convert_to_consistent_units. pre_calc_units must be given as a pint
     Unit or None.
 
@@ -96,7 +96,7 @@ def convert_arg(arg, pre_calc_units):
 
 def convert_to_consistent_units(*args, pre_calc_units=None, **kwargs):
     """Prepare args and kwargs for wrapping by unit conversion and stripping.
-    
+
     If pre_calc_units is not None, takes the args and kwargs for a NumPy function and converts
     any Quantity or Sequence of Quantities into the units of the first Quantiy/Sequence of
     Quantities and returns the magnitudes. Other args/kwargs are treated as dimensionless
@@ -114,7 +114,7 @@ def convert_to_consistent_units(*args, pre_calc_units=None, **kwargs):
 
 def unwrap_and_wrap_consistent_units(*args):
     """Strip units from args while providing a rewrapping function.
-    
+
     Returns the given args as parsed by convert_to_consistent_units assuming units of
     first arg with units, along with a wrapper to restore that unit to the output.
 
@@ -129,9 +129,9 @@ def unwrap_and_wrap_consistent_units(*args):
 
 def get_op_output_unit(unit_op, first_input_units, all_args=None, size=None):
     """Determine resulting unit from given operation.
-    
+
     Options for `unit_op`:
-    
+
     - "sum": `first_input_units`, unless non-multiplicative, which raises
       OffsetUnitCalculusError
     - "mul": product of all units in `all_args`
@@ -149,9 +149,9 @@ def get_op_output_unit(unit_op, first_input_units, all_args=None, size=None):
     Parameters
     ----------
     unit_op :
-        
+
     first_input_units :
-        
+
     all_args :
          (Default value = None)
     size :
@@ -249,7 +249,7 @@ def implement_func(func_type, func_str, input_units=None, output_unit=None):
         `get_op_output_unit`. If some other string, the string is parsed as a unit,
         which becomes the unit of the output. If None, the bare magnitude is returned.
 
-    
+
     """
     # If NumPy is not available, do not attempt implement that which does not exist
     if np is None:
diff --git a/pint/quantity.py b/pint/quantity.py
index 1bf3fb9..8bdf737 100644
--- a/pint/quantity.py
+++ b/pint/quantity.py
@@ -418,7 +418,7 @@ class Quantity(PrettyIPython, SharedRegistryObject):
         """Transforms a list of Quantities into an numpy.array quantity.
         If no units are specified, the unit of the first element will be used.
         Same as from_sequence.
-        
+
         If units is not specified and list is empty, the unit cannot be determined
         and a ValueError is raised.
 
@@ -439,7 +439,7 @@ class Quantity(PrettyIPython, SharedRegistryObject):
     def from_sequence(cls, seq, units=None):
         """Transforms a sequence of Quantities into an numpy.array quantity.
         If no units are specified, the unit of the first element will be used.
-        
+
         If units is not specified and sequence is empty, the unit cannot be determined
         and a ValueError is raised.
 
@@ -1597,7 +1597,7 @@ class Quantity(PrettyIPython, SharedRegistryObject):
 
     def dot(self, b):
         """Dot product of two arrays.
-        
+
         Wraps np.dot().
         """
 
diff --git a/pint/registry.py b/pint/registry.py
index d4f75d3..cfade8b 100644
--- a/pint/registry.py
+++ b/pint/registry.py
@@ -122,9 +122,9 @@ class ContextCacheOverlay:
 
 class BaseRegistry(metaclass=RegistryMeta):
     """Base class for all registries.
-    
+
     Capabilities:
-    
+
     - Register units, prefixes, and dimensions, and their relations.
     - Convert between units.
     - Find dimensionality of a unit.
@@ -329,7 +329,7 @@ class BaseRegistry(metaclass=RegistryMeta):
 
     def _define(self, definition):
         """Add unit to the registry.
-        
+
         This method defines only multiplicative units, converting any other type
         to `delta_` units.
 
@@ -434,7 +434,7 @@ class BaseRegistry(metaclass=RegistryMeta):
 
     def _define_single_adder(self, key, value, unit_dict, casei_unit_dict):
         """Helper function to store a definition in the internal dictionaries.
-        
+
         It warns or raise error on redefinition.
         """
         if key in unit_dict:
@@ -723,7 +723,7 @@ class BaseRegistry(metaclass=RegistryMeta):
 
     def get_root_units(self, input_units, check_nonmult=True):
         """Convert unit or dict of units to the root units.
-        
+
         If any unit is non multiplicative and check_converter is True,
         then None is returned as the multiplicative factor.
 
@@ -750,7 +750,7 @@ class BaseRegistry(metaclass=RegistryMeta):
 
     def _get_root_units(self, input_units, check_nonmult=True):
         """Convert unit or dict of units to the root units.
-        
+
         If any unit is non multiplicative and check_converter is True,
         then None is returned as the multiplicative factor.
 
@@ -794,7 +794,7 @@ class BaseRegistry(metaclass=RegistryMeta):
 
     def get_base_units(self, input_units, check_nonmult=True, system=None):
         """Convert unit or dict of units to the base units.
-        
+
         If any unit is non multiplicative and check_converter is True,
         then None is returned as the multiplicative factor.
 
@@ -937,7 +937,7 @@ class BaseRegistry(metaclass=RegistryMeta):
         Parameters
         ----------
         unit_name :
-            
+
         case_sensitive :
              (Default value = True)
 
@@ -981,10 +981,10 @@ class BaseRegistry(metaclass=RegistryMeta):
     @staticmethod
     def _dedup_candidates(candidates):
         """Helper of parse_unit_name.
-        
+
         Given an iterable of unit triplets (prefix, name, suffix), remove those with
         different names but equal value, preferring those with a prefix.
-        
+
         e.g. ('kilo', 'gram', '') and ('', 'kilogram', '')
         """
         candidates = dict.fromkeys(candidates)  # ordered set
@@ -1000,7 +1000,7 @@ class BaseRegistry(metaclass=RegistryMeta):
     def parse_units(self, input_string, as_delta=None):
         """Parse a units expression and returns a UnitContainer with
         the canonical names.
-        
+
         The expression can only contain products, ratios and powers of units.
 
         Parameters
@@ -1085,20 +1085,20 @@ class BaseRegistry(metaclass=RegistryMeta):
         self, input_string, case_sensitive=True, use_decimal=False, **values
     ):
         """Parse a mathematical expression including units and return a quantity object.
-        
+
         Numerical constants can be specified as keyword arguments and will take precedence
         over the names defined in the registry.
 
         Parameters
         ----------
         input_string :
-            
+
         case_sensitive :
              (Default value = True)
         use_decimal :
              (Default value = False)
         **values :
-            
+
 
         Returns
         -------
@@ -1124,7 +1124,7 @@ class BaseRegistry(metaclass=RegistryMeta):
 
 class NonMultiplicativeRegistry(BaseRegistry):
     """Handle of non multiplicative units (e.g. Temperature).
-    
+
     Capabilities:
     - Register non-multiplicative units and their relations.
     - Convert between non-multiplicative units.
@@ -1163,7 +1163,7 @@ class NonMultiplicativeRegistry(BaseRegistry):
 
     def _define(self, definition):
         """Add unit to the registry.
-        
+
         In addition to what is done by the BaseRegistry,
         registers also non-multiplicative units.
 
@@ -1232,7 +1232,7 @@ class NonMultiplicativeRegistry(BaseRegistry):
 
     def _convert(self, value, src, dst, inplace=False):
         """Convert value from some source to destination units.
-        
+
         In addition to what is done by the BaseRegistry,
         converts between non-multiplicative units.
 
@@ -1304,11 +1304,11 @@ class NonMultiplicativeRegistry(BaseRegistry):
 
 class ContextRegistry(BaseRegistry):
     """Handle of Contexts.
-    
+
     Conversion between units with different dimenstions according
     to previously established relations (contexts).
     (e.g. in the spectroscopy, conversion between frequency and energy is possible)
-    
+
     Capabilities:
     - Register contexts.
     - Enable and disable contexts.
@@ -1344,9 +1344,9 @@ class ContextRegistry(BaseRegistry):
 
     def add_context(self, context: Context) -> None:
         """Add a context object to the registry.
-        
+
         The context will be accessible by its name and aliases.
-        
+
         Notice that this method will NOT enable the context. Use `enable_contexts`.
 
         """
@@ -1367,7 +1367,7 @@ class ContextRegistry(BaseRegistry):
 
     def remove_context(self, name_or_alias: str) -> Context:
         """Remove a context from the registry and return it.
-        
+
         Notice that this methods will not disable the context. Use `disable_contexts`.
 
         """
@@ -1474,7 +1474,7 @@ class ContextRegistry(BaseRegistry):
         kwargs :
             keyword arguments for the context
         *names_or_contexts :
-            
+
         **kwargs :
 
         """
@@ -1535,23 +1535,23 @@ class ContextRegistry(BaseRegistry):
             name of the context.
         kwargs :
             keyword arguments for the contexts.
-            
+
             Context are called by their name::
-            
-            
+
+
             If the context has an argument, you can specify its value as a keyword
             argument::
-            
-            
+
+
             Multiple contexts can be entered in single call:
-            
-            
+
+
             or nested allowing you to give different values to the same keyword argument::
-            
-            
+
+
             A nested context inherits the defaults from the containing context::
         *names :
-            
+
         **kwargs :
 
 
@@ -1586,7 +1586,7 @@ class ContextRegistry(BaseRegistry):
 
     def with_context(self, name, **kw):
         """Decorator to wrap a function call in a Pint context.
-        
+
         Use it to ensure that a certain context is active when
         calling a function::
 
@@ -1597,9 +1597,9 @@ class ContextRegistry(BaseRegistry):
         kwargs :
             keyword arguments for the contexts.
         name :
-            
+
         **kw :
-            
+
 
         Returns
         -------
@@ -1632,7 +1632,7 @@ class ContextRegistry(BaseRegistry):
 
     def _convert(self, value, src, dst, inplace=False):
         """Convert value from some source to destination units.
-        
+
         In addition to what is done by the BaseRegistry,
         converts between units with different dimensions by following
         transformation rules defined in the context.
@@ -1693,11 +1693,11 @@ class ContextRegistry(BaseRegistry):
 
 class SystemRegistry(BaseRegistry):
     """Handle of Systems and Groups.
-    
+
     Conversion between units with different dimenstions according
     to previously established relations (contexts).
     (e.g. in the spectroscopy, conversion between frequency and energy is possible)
-    
+
     Capabilities:
     - Register systems and groups.
     - List systems
@@ -1729,7 +1729,7 @@ class SystemRegistry(BaseRegistry):
 
     def _after_init(self):
         """After init function
-        
+
         Create default group.
         Add all orphan units to it.
         Set default system.
@@ -1847,10 +1847,10 @@ class SystemRegistry(BaseRegistry):
 
     def get_base_units(self, input_units, check_nonmult=True, system=None):
         """Convert unit or dict of units to the base units.
-        
+
         If any unit is non multiplicative and check_converter is True,
         then None is returned as the multiplicative factor.
-        
+
         Unlike BaseRegistry, in this registry root_units might be different
         from base_units
 
diff --git a/pint/registry_helpers.py b/pint/registry_helpers.py
index 6bd21dd..d51daba 100644
--- a/pint/registry_helpers.py
+++ b/pint/registry_helpers.py
@@ -45,14 +45,14 @@ def _to_units_container(a, registry=None):
     Parameters
     ----------
     a :
-        
+
     registry :
          (Default value = None)
 
     Returns
     -------
     UnitsContainer, bool
-        
+
 
     """
     if isinstance(a, str) and "=" in a:
@@ -154,7 +154,7 @@ def _parse_wrap_args(args, registry=None):
 
 def _apply_defaults(func, args, kwargs):
     """Apply default keyword arguments.
-    
+
     Named keywords may have been left blank. This function applies the default
     values so that every argument is defined.
     """
@@ -170,15 +170,15 @@ def _apply_defaults(func, args, kwargs):
 
 def wraps(ureg, ret, args, strict=True):
     """Wraps a function to become pint-aware.
-    
+
     Use it when a function requires a numerical value but in some specific
     units. The wrapper function will take a pint quantity, convert to the units
     specified in `args` and then call the wrapped function with the resulting
     magnitude.
-    
+
     The value returned by the wrapped function will be converted to the units
     specified in `ret`.
-    
+
     Use None to skip argument conversion.
     Set strict to False, to accept also numerical values.
 
@@ -256,10 +256,10 @@ def wraps(ureg, ret, args, strict=True):
 
 def check(ureg, *args):
     """Decorator to for quantity type checking for function inputs.
-    
+
     Use it to ensure that the decorated function input parameters match
     the expected type of pint quantity.
-    
+
     Use None to skip argument checking.
 
     Parameters
@@ -269,7 +269,7 @@ def check(ureg, *args):
     args :
         iterable of input units.
     *args :
-        
+
 
     Returns
     -------
diff --git a/pint/systems.py b/pint/systems.py
index 198baf2..fc8c532 100644
--- a/pint/systems.py
+++ b/pint/systems.py
@@ -26,16 +26,16 @@ from .util import (
 
 class Group(SharedRegistryObject):
     """A group is a set of units.
-    
+
     Units can be added directly or by including other groups.
-    
+
     Members are computed dynamically, that is if a unit is added to a group X
     all groups that include X are affected.
-    
+
     The group belongs to one Registry.
-    
+
     It can be specified in the definition file as::
-    
+
         @group <name> [using <group 1>, ..., <group N>]
             <definition 1>
             ...
@@ -86,7 +86,7 @@ class Group(SharedRegistryObject):
     @property
     def members(self):
         """Names of the units that are members of the group.
-        
+
         Calculated to include to all units in all included _used_groups.
 
         """
@@ -242,28 +242,28 @@ class Group(SharedRegistryObject):
 
 class System(SharedRegistryObject):
     """A system is a Group plus a set of base units.
-    
+
     Members are computed dynamically, that is if a unit is added to a group X
     all groups that include X are affected.
-    
+
     The System belongs to one Registry.
-    
+
     It can be specified in the definition file as::
-    
+
         @system <name> [using <group 1>, ..., <group N>]
             <rule 1>
             ...
             <rule N>
         @end
-    
+
     The syntax for the rule is:
-    
+
         new_unit_name : old_unit_name
-    
+
     where:
         - old_unit_name: a root unit part which is going to be removed from the system.
         - new_unit_name: a non root unit which is going to replace the old_unit.
-    
+
     If the new_unit_name and the old_unit_name, the later and the colon can be ommited.
     """
 
diff --git a/pint/testsuite/__init__.py b/pint/testsuite/__init__.py
index bd384d6..1614f59 100644
--- a/pint/testsuite/__init__.py
+++ b/pint/testsuite/__init__.py
@@ -143,7 +143,7 @@ def main():
 
 def run():
     """Run all tests.
-    
+
     :return: a :class:`unittest.TestResult` object
 
     Parameters
@@ -173,7 +173,7 @@ def add_docs(suite):
     Parameters
     ----------
     suite :
-        
+
 
     Returns
     -------
diff --git a/pint/testsuite/parameterized.py b/pint/testsuite/parameterized.py
index ee4917d..8e5df98 100644
--- a/pint/testsuite/parameterized.py
+++ b/pint/testsuite/parameterized.py
@@ -109,7 +109,7 @@ class ParameterizedTestMixin(metaclass=ParameterizedTestCaseMetaClass):
         cls, param_names, data, func_name_format="{func_name}_{case_num:05d}"
     ):
         """Decorator for parameterizing a test method - example:
-        
+
         @ParameterizedTestCase.parameterize(
             ("isbn", "expected_title"), [
                 ("0262033844", "Introduction to Algorithms"),
@@ -118,9 +118,9 @@ class ParameterizedTestMixin(metaclass=ParameterizedTestCaseMetaClass):
         Parameters
         ----------
         param_names :
-            
+
         data :
-            
+
         func_name_format :
              (Default value = "{func_name}_{case_num:05d}")
 
diff --git a/pint/testsuite/test_issues.py b/pint/testsuite/test_issues.py
index 04aa31d..8d6bd7e 100644
--- a/pint/testsuite/test_issues.py
+++ b/pint/testsuite/test_issues.py
@@ -527,21 +527,21 @@ class TestIssues(QuantityTestCase):
         @ureg.wraps(ureg.second, (ureg.meters, ureg.meters / ureg.second ** 2))
         def calculate_time_to_fall(height, gravity=Q_(9.8, "m/s^2")):
             """Calculate time to fall from a height h with a default gravity.
-            
+
             By default, the gravity is assumed to be earth gravity,
             but it can be modified.
-            
+
             d = .5 * g * t**2
             t = sqrt(2 * d / g)
 
             Parameters
             ----------
             height :
-                
+
             gravity :
                  (Default value = Q_(9.8)
             "m/s^2") :
-                
+
 
             Returns
             -------
@@ -568,11 +568,11 @@ class TestIssues(QuantityTestCase):
             Parameters
             ----------
             time :
-                
+
             rate :
                  (Default value = Q_(1)
             "m/s") :
-                
+
 
             Returns
             -------
diff --git a/pint/testsuite/test_numpy.py b/pint/testsuite/test_numpy.py
index 72fa70e..3f2bce1 100644
--- a/pint/testsuite/test_numpy.py
+++ b/pint/testsuite/test_numpy.py
@@ -1124,9 +1124,9 @@ class TestNumpyUnclassified(TestNumpyMethods):
 @unittest.skip
 class TestBitTwiddlingUfuncs(TestUFuncs):
     """Universal functions (ufuncs) >  Bittwiddling functions
-    
+
     http://docs.scipy.org/doc/numpy/reference/ufuncs.html#bittwiddlingfunctions
-    
+
     bitwise_and(x1, x2[, out])         Compute the bitwise AND of two arrays elementwise.
     bitwise_or(x1, x2[, out])  Compute the bitwise OR of two arrays elementwise.
     bitwise_xor(x1, x2[, out])         Compute the bitwise XOR of two arrays elementwise.
diff --git a/pint/testsuite/test_umath.py b/pint/testsuite/test_umath.py
index 60559ed..75b7365 100644
--- a/pint/testsuite/test_umath.py
+++ b/pint/testsuite/test_umath.py
@@ -146,7 +146,7 @@ class TestUFuncs(QuantityTestCase):
         rtol :
             relative tolerance. (Default value = 1e-6)
         "same") :
-            
+
 
         Returns
         -------
@@ -271,9 +271,9 @@ class TestUFuncs(QuantityTestCase):
 @helpers.requires_numpy()
 class TestMathUfuncs(TestUFuncs):
     """Universal functions (ufunc) > Math operations
-    
+
     http://docs.scipy.org/doc/numpy/reference/ufuncs.html#math-operations
-    
+
     add(x1, x2[, out]) 	Add arguments element-wise.
     subtract(x1, x2[, out]) 	Subtract arguments, element-wise.
     multiply(x1, x2[, out]) 	Multiply arguments element-wise.
@@ -419,9 +419,9 @@ class TestMathUfuncs(TestUFuncs):
 @helpers.requires_numpy()
 class TestTrigUfuncs(TestUFuncs):
     """Universal functions (ufunc) > Trigonometric functions
-    
+
     http://docs.scipy.org/doc/numpy/reference/ufuncs.html#trigonometric-functions
-    
+
     sin(x[, out]) 	Trigonometric sine, element-wise.
     cos(x[, out]) 	Cosine elementwise.
     tan(x[, out]) 	Compute tangent element-wise.
@@ -676,9 +676,9 @@ class TestTrigUfuncs(TestUFuncs):
 
 class TestComparisonUfuncs(TestUFuncs):
     """Universal functions (ufunc) > Comparison functions
-    
+
     http://docs.scipy.org/doc/numpy/reference/ufuncs.html#comparison-functions
-    
+
     greater(x1, x2[, out]) 	Return the truth value of (x1 > x2) element-wise.
     greater_equal(x1, x2[, out]) 	Return the truth value of (x1 >= x2) element-wise.
     less(x1, x2[, out]) 	Return the truth value of (x1 < x2) element-wise.
@@ -715,9 +715,9 @@ class TestComparisonUfuncs(TestUFuncs):
 
 class TestFloatingUfuncs(TestUFuncs):
     """Universal functions (ufunc) > Floating functions
-    
+
     http://docs.scipy.org/doc/numpy/reference/ufuncs.html#floating-functions
-    
+
     isreal(x) 	Returns a bool array, where True if input element is real.
     iscomplex(x) 	Returns a bool array, where True if input element is complex.
     isfinite(x[, out]) 	Test element-wise for finite-ness (not infinity or not Not a Number).
diff --git a/pint/util.py b/pint/util.py
index fe3c172..aff507b 100644
--- a/pint/util.py
+++ b/pint/util.py
@@ -37,7 +37,7 @@ def matrix_to_string(
     Parameters
     ----------
     matrix :
-        
+
     row_headers :
          (Default value = None)
     col_headers :
@@ -69,7 +69,7 @@ def transpose(matrix):
     Parameters
     ----------
     matrix :
-        
+
 
     Returns
     -------
@@ -305,7 +305,7 @@ class udict(dict):
 class UnitsContainer(Mapping):
     """The UnitsContainer stores the product of units and their respective
     exponent and implements the corresponding operations.
-    
+
     UnitsContainer is a read-only mapping. All operations (even in place ones)
 
     Parameters
@@ -314,7 +314,7 @@ class UnitsContainer(Mapping):
     Returns
     -------
     type
-        
+
 
     """
 
@@ -351,7 +351,7 @@ class UnitsContainer(Mapping):
         Parameters
         ----------
         keys :
-            
+
 
         Returns
         -------
@@ -369,9 +369,9 @@ class UnitsContainer(Mapping):
         Parameters
         ----------
         oldkey :
-            
+
         newkey :
-            
+
 
         Returns
         -------
@@ -490,7 +490,7 @@ class UnitsContainer(Mapping):
 class ParserHelper(UnitsContainer):
     """The ParserHelper stores in place the product of variables and
     their respective exponent and implements the corresponding operations.
-    
+
     ParserHelper is a read-only mapping. All operations (even in place ones)
 
     Parameters
@@ -514,13 +514,13 @@ class ParserHelper(UnitsContainer):
     @classmethod
     def from_word(cls, input_word):
         """Creates a ParserHelper object with a single variable with exponent one.
-        
+
         Equivalent to: ParserHelper({'word': 1})
 
         Parameters
         ----------
         input_word :
-            
+
 
         Returns
         -------
@@ -552,7 +552,7 @@ class ParserHelper(UnitsContainer):
         Parameters
         ----------
         input_string :
-            
+
 
         Returns
         -------
@@ -736,7 +736,7 @@ def _is_dim(name):
 
 class SharedRegistryObject:
     """Base class for object keeping a reference to the registree.
-    
+
     Such object are for now Quantity and Unit, in a number of places it is
     that an object from this class has a '_units' attribute.
 
@@ -765,7 +765,7 @@ class SharedRegistryObject:
         Parameters
         ----------
         other :
-            
+
 
         Returns
         -------
@@ -814,7 +814,7 @@ def to_units_container(unit_like, registry=None):
     Parameters
     ----------
     unit_like :
-        
+
     registry :
          (Default value = None)
 
@@ -842,12 +842,12 @@ def infer_base_unit(q):
     Parameters
     ----------
     q :
-        
+
 
     Returns
     -------
     type
-        
+
 
     """
     d = udict()
@@ -868,7 +868,7 @@ def getattr_maybe_raise(self, item):
     Parameters
     ----------
     item :
-        
+
 
     Returns
     -------
@@ -882,12 +882,12 @@ def getattr_maybe_raise(self, item):
 
 class SourceIterator:
     """Iterator to facilitate reading the definition files.
-    
+
     Accepts any sequence (like a list of lines, a file or another SourceIterator)
-    
+
     The iterator yields the line number and line (skipping comments and empty lines)
     and stripping white spaces.
-    
+
     for lineno, line in SourceIterator(sequence):
         # do something here
 
@@ -954,7 +954,7 @@ class BlockIterator(SourceIterator):
 
 def iterable(y):
     """Check whether or not an object can be iterated over.
-    
+
     Vendored from numpy under the terms of the BSD 3-Clause License. (Copyright
     (c) 2005-2019, NumPy Developers.)