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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 unpack_zipfile(filename):
 """Unpack a zipfile, using the names in the zip."""

    with open(filename, "rb") as fzip:
        z = zipfile.ZipFile(fzip)
        for name in z.namelist():
            print(("      extracting {}".format(name)))
            ensure_dirs(name)
            z.extract(name)