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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 merge_envs(*args):
 """Union of one or more dictionaries. In case of duplicate keys, the values in the right-most arguments will squash (overwrite) the value provided by any dict preceding it. :param args: Sequence of ``dict`` objects that should be merged. :return: A ``dict`` containing the union of keys in all input dicts. """

    env = {}
    for arg in args:
        if not arg:
            continue
        env.update(arg)
    return env