code: public static function create(
          array $parameters,
          $beforeKey = 'before',
          $afterKey = 'after',
          $limitKey = 'limit'
      ) {
          return new self(
              array_get($parameters, $beforeKey),
              array_get($parameters, $afterKey),
              array_get($parameters, $limitKey, 15)
          );
      }
docs: Create a cursor from query parameters.
  
  @param array $parameters
  @param string $beforeKey
  @param string $afterKey
  @param string $limitKey
  @return Cursor