code: public function chargesRetrieve($id, $expand = null)
      {
          list($response) = $this->chargesRetrieveWithHttpInfo($id, $expand);
          return $response;
      }
docs: Operation chargesRetrieve
  
  Retrieve a charge
  
  @param string $id The id of the charge (required)
  @param string $expand Allows expanding related entities in the response. Only valid entry is &#39;customer&#39; (optional)
  @throws \zipMoney\ApiException on non-2xx response
  @return \zipMoney\Model\Charge