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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 inject_default_call(self, high):
        '''
        Sets .call function to a state, if not there.

        :param high:
        :return:
        '''
        for chunk in high:
            state = high[chunk]
            if not isinstance(state, collections.Mapping):
                continue
            for state_ref in state:
                needs_default = True
                if not isinstance(state[state_ref], list):
                    continue
                for argset in state[state_ref]:
                    if isinstance(argset, six.string_types):
                        needs_default = False
                        break
                if needs_default:
                    state[state_ref].insert(-1, '__call__')