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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 get_version(version):
 """Dynamically calculate the version based on VERSION tuple."""

    if len(version) > 2 and version[2] is not None:
        if isinstance(version[2], int):
            str_version = "%s.%s.%s" % version[:3]
        else:
            str_version = "%s.%s_%s" % version[:3]
    else:
        str_version = "%s.%s" % version[:2]

    return str_version