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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 add_predicate(self, predicate):
 """ Add a new predicate callback to this handler. """

        _predicate = predicate
        if isinstance(predicate, partial):
            _predicate = 'partial(%s, %s, %s)' % (predicate.func, predicate.args, predicate.keywords)
        if LOG_OPTS['register']:
            hookenv.log('  Adding predicate for %s: %s' % (self.id(), _predicate), level=hookenv.DEBUG)
        self._predicates.append(predicate)