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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 version_str2tuple(cls, version_str):
 """Version info. tuple object. ex. ('4', '14', '0', 'rc1') """

        if not isinstance(version_str, str):
            ValueError('version_str invalid instance.')
        version_info_list = re.findall(r'[0-9a-zA-Z]+', version_str)

        def convert_to_int(string):
            value = None
            if re.match(r'^\d+$', string):
                value = int(string)
            else:
                value = string
            return value

        version_info_list = [convert_to_int(s) for s in version_info_list]

        return tuple(version_info_list)