@rule('<STR_LIT>')<EOL><INDENT>def visit_oper(self, node, _):<DEDENT>
oper = node.text<EOL>if oper == '<STR_LIT::>':<EOL><INDENT>oper = '<STR_LIT:=>'<EOL><DEDENT>return oper<EOL>
Return an operator as a string. Currently only "=" and ":" (both synonyms)

        Arguments
        ---------
        node : parsimonious.nodes.Node.
        _ (children) : list, unused

        Result
        ------
        str
            The operator as a string.

        Example
        -------

        >>> BaseParser('=', default_rule='OPER').data
        '='
        >>> BaseParser(':', default_rule='OPER').data
        '='