'Add patterns chain, using configuration from this chain
:return:
:rtype:'

def chain(self):

    chain = self.rebulk.chain(**self._kwargs)
    chain._defaults = dict(self._defaults)
    chain._regex_defaults = dict(self._regex_defaults)
    chain._functional_defaults = dict(self._functional_defaults)
    chain._string_defaults = dict(self._string_defaults)
    return chain
