code: def project_groups(self, key, limit=99999, filter_str=None):
          
          url = 'rest/api/1.0/projects/{key}/permissions/groups'.format(key=key)
          params = {}
          if limit:
              params['limit'] = limit
          if filter_str:
              params['filter'] = filter_str
          return (self.get(url, params=params) or {}).get('values')
docs: Get Project Groups
          :param key:
          :param limit: OPTIONAL: The limit of the number of groups to return, this may be restricted by
                              fixed system limits. Default by built-in method: 99999
          :param filter_str: OPTIONAL: group filter string
          :return: