def fields(self):
        """
        Return the fields specified in the pattern using Python's
        formatting mini-language.
        """
        parse = list(string.Formatter().parse(self.pattern))
        return [f for f in zip(*parse)[1] if f is not None]
def fields(self):
        """
        Return the fields specified in the pattern using Python's
        formatting mini-language.
        """
        parse = list(string.Formatter().parse(self.pattern))
        return [f for f in zip(*parse)[1] if f is not None]
def fields ( self ) : parse = list ( string . Formatter ( ) . parse ( self . pattern ) ) return [ f for f in zip ( * parse ) [ 1 ] if f is not None ]
Return the fields specified in the pattern using Python's
        formatting mini-language.
Return the fields specified in the pattern using Python s formatting mini - language .