docs: def _man_args(self, f):
          """
          Returns number of mandatory arguments required by given function.
          """
          argcount = f.func_code.co_argcount
  
          # account for "self" getting passed to class instance methods
          if isinstance(f, types.MethodType):
              argcount -= 1
  
          if f.func_defaults is None:
              return argcount
  
          return argcount - len(f.func_defaults)