original_string: public function setHeader($keyName, $value)
      {
          $normalizedKeyName = self::normalizeHeaderKeyName($keyName);
          $this->headers[$normalizedKeyName] = $value;
      }
code: public function setHeader($keyName, $value)
      {
          $normalizedKeyName = self::normalizeHeaderKeyName($keyName);
          $this->headers[$normalizedKeyName] = $value;
      }
code_tokens: public function setHeader ( $ keyName , $ value ) { $ normalizedKeyName = self :: normalizeHeaderKeyName ( $ keyName ) ; $ this -> headers [ $ normalizedKeyName ] = $ value ; }
docstring: Set a header. If it already exists the value is overwritten with the
  new one.
  
  @param string     $keyName the name of the header
  @param string|int $value   the value of the header
docstring_tokens: Set a header . If it already exists the value is overwritten with the new one .