Sets up the constant regex strings etc. that can be used to
        parse the strings for determining context.

def _setup_regex(self):
        """Sets up the constant regex strings etc. that can be used to
        parse the strings for determining context."""
        self.RE_COMMENTS = cache.RE_COMMENTS
        self.RE_MODULE = cache.RE_MODULE
        self.RE_TYPE = cache.RE_TYPE
        self.RE_EXEC = cache.RE_EXEC
        self.RE_MEMBERS = cache.RE_MEMBERS
        self.RE_DEPEND = cache.RE_DEPEND