fix pydoc.apropos and pydoc.synopsis on modules with empty docstrings (#21548)

Patch by Yuyang Guo and Berker Peksag.

1 files changed, 2 insertions, 2 deletions

diff --git a/Lib/pydoc.py b/Lib/pydoc.py
index d53a1b4b7e..d37ebf12db 100755
--- a/Lib/pydoc.py
+++ b/Lib/pydoc.py
@@ -270,7 +270,7 @@ def synopsis(filename, cache={}):
             except:
                 return None
             del sys.modules['__temp__']
-            result = (module.__doc__ or '').splitlines()[0]
+            result = module.__doc__.splitlines()[0] if module.__doc__ else None
         # Cache the result.
         cache[filename] = (mtime, result)
     return result
@@ -2075,7 +2075,7 @@ class ModuleScanner:
                         if onerror:
                             onerror(modname)
                         continue
-                    desc = (module.__doc__ or '').splitlines()[0]
+                    desc = module.__doc__.splitlines()[0] if module.__doc__ else ''
                     path = getattr(module,'__file__',None)
                 name = modname + ' - ' + desc
                 if name.lower().find(key) >= 0: