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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 return_abs_path(directory, path):
 """ Unfortunately, Python is not smart enough to return an absolute path with tilde expansion, so I writing functionality to do this :param directory: :param path: :return: """

    if directory is None or path is None:
        return
    directory = os.path.expanduser(directory)
    return os.path.abspath(os.path.join(directory, path))