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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 check_assertions(self, checklist, all=False):
 """Check a set of assertions @param all boolean if False, stop at first failure @return: False if any assertion fails. """


        assert isinstance(checklist, dict) and 'checks' in checklist

        retval = None
        retlist = []

        for assertion in checklist['checks']:
            retval = self.check_assertion(**assertion)
            retlist.append(retval)
            if not retval.success and not all:
                print "Error message:", retval[3]
                return retlist

        return retlist