'Retrieve the value of the I{Host} header from the serialized
request given by C{bytes}.'

def _getHost(self, bytes):

    for line in bytes.split('\r\n'):
        try:
            (name, value) = line.split(':', 1)
            if (name.strip().lower() == 'host'):
                return value.strip()
        except ValueError:
            pass
