code: def _filter_kwargs(self, keep_list, **kwargs):
          ''' Filters the dict of *kwargs*, keeping only arguments 
              whose keys are in *keep_list* and discarding all other
              arguments.
              
              Based on the filtring, constructs and returns a new 
              dict.
          '''
          new_kwargs = {}
          for argName, argVal in kwargs.items():
              if argName.lower() in keep_list:
                  new_kwargs[argName.lower()] = argVal
          return new_kwargf _filter_kwargs(self, keep_list, **kwargs):
          ''' Filters the dict of *kwargs*, keeping only arguments 
              whose keys are in *keep_list* and discarding all other
              arguments.
              
              Based on the filtring, constructs and returns a new 
              dict.
          '''
          new_kwargs = {}
          for argName, argVal in kwargs.items():
              if argName.lower() in keep_list:
                  new_kwargs[argName.lower()] = argVal
          return new_kwargs
docs: Filters the dict of *kwargs*, keeping only arguments 
              whose keys are in *keep_list* and discarding all other
              arguments.
              
              Based on the filtring, constructs and returns a new 
              dict.