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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 assert_is_not(first, second, msg_fmt="{msg}"):
 """Fail if first and second refer to the same object. Traceback (most recent call last):
 AssertionError: both arguments refer to [5, 'foo'] The following msg_fmt arguments are supported: * msg - the default error message * first - the first argument * second - the second argument """


    if first is second:
        msg = "both arguments refer to {!r}".format(first)
        fail(msg_fmt.format(msg=msg, first=first, second=second))