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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def bind(self, fn):
        '''This is the monadic binding operation. Returns a parser which, if
        parser is successful, passes the result to fn, and continues with the
        parser returned from fn.
        '''
        @Parser
        def bind_parser(text, index):
            res = self(text, index)
            return res if not res.status else fn(res.value)(text, res.index)
        return bind_parser