How to use the numerapi.utils function in numerapi

number
                  openTime
                  resolveTime
                  resolvedGeneral
                  resolvedStaking
                }
              }
            }
          }
        """
        data = self.raw_query(query, authorization=True)['data']
        payments = data['user']
        # convert strings to python objects
        for p in payments['payments']:
            utils.replace(p['round'], "openTime", utils.parse_datetime_string)
            utils.replace(p['round'], "resolveTime",
                          utils.parse_datetime_string)
            utils.replace(p, "usdAmount", utils.parse_float_string)
            utils.replace(p, "nmrAmount", utils.parse_float_string)
        for p in payments['reputationPayments']:
            utils.replace(p, "nmrAmount", utils.parse_float_string)
            utils.replace(p, "insertedAt", utils.parse_datetime_string)
        for p in payments['otherUsdIssuances']:
            utils.replace(p, "usdAmount", utils.parse_float_string)
            utils.replace(p, "insertedAt", utils.parse_datetime_string)
        return payments

query = '''
          mutation($value: String!
                   $type: String!) {
              v2ChangeStake(value: $value
                            type: $type) {
                dueDate
                requestedAmount
                status
                type
              }
        }
        '''
        arguments = {'value': str(nmr), 'type': action}
        result = self.raw_query(query, arguments, authorization=True)
        stake = result['data']['v2ChangeStake']
        utils.replace(stake, "requestedAmount", utils.parse_float_string)
        utils.replace(stake, "dueDate", utils.parse_datetime_string)
        return stake

openTime
                resolvedGeneral
                resolvedStaking
                participants
                prizePoolNmr
                prizePoolUsd
                ruleset
              }
            }
        '''
        arguments = {'tournament': tournament}
        result = self.raw_query(query, arguments)
        rounds = result['data']['rounds']
        # convert datetime strings to datetime.datetime objects
        for r in rounds:
            utils.replace(r, "openTime", utils.parse_datetime_string)
            utils.replace(r, "resolveTime", utils.parse_datetime_string)
            utils.replace(r, "prizePoolNmr", utils.parse_float_string)
            utils.replace(r, "prizePoolUsd", utils.parse_float_string)
        return rounds