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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 validate_tgt(self, valid, expr, tgt_type, minions=None, expr_form=None):
        '''
        Return a Bool. This function returns if the expression sent in is
        within the scope of the valid expression
        '''

        v_minions = set(self.check_minions(valid, 'compound').get('minions', []))
        if minions is None:
            _res = self.check_minions(expr, tgt_type)
            minions = set(_res['minions'])
        else:
            minions = set(minions)
        d_bool = not bool(minions.difference(v_minions))
        if len(v_minions) == len(minions) and d_bool:
            return True
        return d_bool