code: def find_module(self, modname, folder=None):
          
          for src in self.get_source_folders():
              module = _find_module_in_folder(src, modname)
              if module is not None:
                  return module
          for src in self.get_python_path_folders():
              module = _find_module_in_folder(src, modname)
              if module is not None:
                  return module
          if folder is not None:
              module = _find_module_in_folder(folder, modname)
              if module is not None:
                  return module
          return None
docs: Returns a resource corresponding to the given module
  
          returns None if it can not be found