original_string: public function sendReminder($method = null)
      {
          if ($method) {
              if (!in_array($method, array('Email', 'Letter')))
                  throw new InvalidFieldValueError("'method' must be either " .
                      "'Email' or 'Letter'");
  
              return $this->performEvent('remind', array('method' => $method));
          }
  
          return $this->performEvent('remind');
      }
code: public function sendReminder($method = null)
      {
          if ($method) {
              if (!in_array($method, array('Email', 'Letter')))
                  throw new InvalidFieldValueError("'method' must be either " .
                      "'Email' or 'Letter'");
  
              return $this->performEvent('remind', array('method' => $method));
          }
  
          return $this->performEvent('remind');
      }
code_tokens: public function sendReminder ( $ method = null ) { if ( $ method ) { if ( ! in_array ( $ method , array ( 'Email' , 'Letter' ) ) ) throw new InvalidFieldValueError ( "'method' must be either " . "'Email' or 'Letter'" ) ; return $ this -> performEvent ( 'remind' , array ( 'method' => $ method ) ) ; } return $ this -> performEvent ( 'remind' ) ; }
docstring: Manually send a reminder if the billogram is overdue.
  
  @param null $method
  @return $this
  @throws \Billogram\Api\Exceptions\InvalidFieldValueError
docstring_tokens: Manually send a reminder if the billogram is overdue .