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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 python_version_matchers():
 """Return set of string representations of current python version"""

    version = sys.version_info
    patterns = [
        "{0}",
        "{0}{1}",
        "{0}.{1}",
    ]
    matchers = [
        pattern.format(*version)
        for pattern in patterns
    ] + [None]
    return set(matchers)