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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 save_file(fullpath, entry):
 """ Save a message file out, without mangling the headers """

    with tempfile.NamedTemporaryFile('w', delete=False) as file:
        tmpfile = file.name
        # we can't just use file.write(str(entry)) because otherwise the
        # headers "helpfully" do MIME encoding normalization.
        # str(val) is necessary to get around email.header's encoding
        # shenanigans
        for key, val in entry.items():
            print('{}: {}'.format(key, str(val)), file=file)
        print('', file=file)
        file.write(entry.get_payload())
    shutil.move(tmpfile, fullpath)