takes an value and returns a tuple of the parts

        args:
            value: a uri in any form pyuri, ttl or full IRI

def get_uri_parts(self, value):
        """takes an value and returns a tuple of the parts

        args:
            value: a uri in any form pyuri, ttl or full IRI
        """
        if value.startswith('pyuri_'):
            value = self.rpyhttp(value)
        parts = self.parse_uri(value)
        try:
            return (self.ns_dict[parts[0]], parts[1])
        except KeyError:
            try:
                return (self.ns_dict[parts[0].lower()], parts[1])
            except KeyError:
                return ((None, parts[0]), parts[1])