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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 compare(ver1, ver2):
 """Compare two versions :param ver1: version string 1 :param ver2: version string 2 :return: The return value is negative if ver1 < ver2, zero if ver1 == ver2 and strictly positive if ver1 > ver2 :rtype: int -1 1 0 """


    v1, v2 = parse(ver1), parse(ver2)

    return _compare_by_keys(v1, v2)