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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 tag_new_version(version: str):
 """ Creates a new tag with the version number prefixed with v. :param version: The version number used in the tag as a string. """


    check_repo()
    return repo.git.tag('-a', 'v{0}'.format(version), m='v{0}'.format(version))