Parse HTTP status line, return status (int) and reason.

def header_status(header):
    """Parse HTTP status line, return status (int) and reason."""
    status_line = header[:header.find('\r')]
    # 'HTTP/1.1 200 OK' -> (200, 'OK')
    fields = status_line.split(None, 2)
    return int(fields[1]), fields[2]