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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 _always_strings(env_dict):
 """ On Windows and Python 2, environment dictionaries must be strings and not unicode. """

    if IS_WINDOWS or PY2:
        env_dict.update((key, str(value)) for (key, value) in env_dict.items())
    return env_dict