def parse_http_header(header, header_key):

    """
        **Parse HTTP header value**

        Parse the value of a specific header from a RAW HTTP response.

        :param header: String containing the RAW HTTP response and headers
        :type header: str
        :param header_key: The header name of which to extract a value from
        :type header_key: str
        :return: The value of the header
        :rtype: str
    """

    split_headers = header.split('\r\n')

    for entry in split_headers:
        header = entry.strip().split(':', 1)

        if header[0].strip().lower() == header_key.strip().lower():
            return ''.join(header[1::]).split()[0]