docs: def get_dependencies(self, version=None):
          '''
          Parameters
          ----------
          version: str
              string representing version number whose dependencies you are
              looking up
          '''
  
          version = _process_version(self, version)
          history = self.get_history()
  
          for v in reversed(history):
              if BumpableVersion(v['version']) == version:
                  return v['dependencies']
  
          raise ValueError('Version {} not found'.format(version))