'Look up a domain name in this dictionary.
@type key: L{bytes}
@param key: A domain name.
@type default: L{IDomain} provider or L{None}
@param default: A domain object to be returned if the domain name is
not in this dictionary.
@rtype: L{IDomain} provider or L{None}
@return: The domain object associated with the domain name if it is in
this dictionary.  Otherwise, the default value.'

def get(self, key, default=None):

    return self.domains.get(key, default)
