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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_in(first, second, msg_fmt="{msg}"):
 """Fail if first is not in collection second. Traceback (most recent call last):
 AssertionError: 'bar' not in [4, 'foo', {}] The following msg_fmt arguments are supported: * msg - the default error message * first - the element looked for * second - the container looked in """


    if first not in second:
        msg = "{!r} not in {!r}".format(first, second)
        fail(msg_fmt.format(msg=msg, first=first, second=second))