code: protected function doReplacement($inputString)
      {
          if (is_string($inputString)) {
              $inputString = str_replace(
                  array_keys($this->replacements),
                  array_values($this->replacements),
                  $inputString
              );
          }
  
          return $inputString;
      }
docs: Applies replacements to provided string.
  
  @param string $inputString
  
  @return string