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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 disttar_suffix(env, sources):
 """tar archive suffix generator"""


        env_dict = env.Dictionary()
        if env_dict.has_key("DISTTAR_FORMAT") and env_dict["DISTTAR_FORMAT"] in ["gz", "bz2"]:
                return ".tar." + env_dict["DISTTAR_FORMAT"]
        else:
                return ".tar"