docs: def service_param_string(params):
      """Takes a param section from a metadata class and returns a param string for the service method"""
      p = []
      k = []
      for param in params:
          name = fix_param_name(param['name'])
          if 'required' in param and param['required'] is True:
              p.append(name)
          else:
              if 'default' in param:
                  k.append('{name}={default}'.format(name=name, default=param['default']))
              else:
                  k.append('{name}=None'.format(name=name))
      p.sort(lambda a, b: len(a) - len(b))
      k.sort()
      a = p + k
      return ', '.join(a)