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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 mode(self, predicate, args, recall=1, head=False):
        '''
        Emits mode declarations in Aleph-like format.

            :param predicate: predicate name
            :param args: predicate arguments with input/output specification, e.g.:

            >>> [('+', 'train'), ('-', 'car')]

            :param recall: recall setting (see `Aleph manual <http://www.cs.ox.ac.uk/activities/machinelearning/Aleph/aleph>`_)
            :param head: set to True for head clauses
        '''
        return ':- mode%s(%s, %s(%s)).' % (
            'h' if head else 'b', str(recall), predicate, ','.join([t + arg for t, arg in args]))