code: def modules(self, filters=None):
          
  
          masks = compile_masks(r'\.py$')
          for file_ in self.files(filters=filters):
              if matches_masks(file_, masks):
                  yield file_
docs: A generator that produces a sequence of paths to files that look to be
          Python modules (e.g., ``*.py``).
  
          :param filters:
              the regular expressions to use when finding files in the project.
              If not specified, all files are returned.
          :type filters: list(str)