def fromString(cls, string):
        """
        Parse a plain-text entry in a known_hosts file, and return a
        corresponding L{PlainEntry}.

        @param string: a space-separated string formatted like "hostname
        key-type base64-key-data comment".

        @type string: L{bytes}

        @raise DecodeError: if the key is not valid encoded as valid base64.

        @raise InvalidEntry: if the entry does not have the right number of
        elements and is therefore invalid.

        @raise BadKeyError: if the key, once decoded from base64, is not
        actually an SSH key.

        @return: an IKnownHostEntry representing the hostname and key in the
        input line.

        @rtype: L{PlainEntry}
        """
        hostnames, keyType, key, comment = _extractCommon(string)
        self = cls(hostnames.split(b","), keyType, key, comment)
        return self

        Parse a plain-text entry in a known_hosts file, and return a
        corresponding L{PlainEntry}.

        @param string: a space-separated string formatted like "hostname
        key-type base64-key-data comment".

        @type string: L{bytes}

        @raise DecodeError: if the key is not valid encoded as valid base64.

        @raise InvalidEntry: if the entry does not have the right number of
        elements and is therefore invalid.

        @raise BadKeyError: if the key, once decoded from base64, is not
        actually an SSH key.

        @return: an IKnownHostEntry representing the hostname and key in the
        input line.

        @rtype: L{PlainEntry}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/client/knownhosts.py