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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 release(major=False, minor=False, patch=True, pypi_index=None):
 """Overall process flow for performing a release"""

    relver = next_release(major, minor, patch)
    start_rel_branch(relver)
    prepare_release(relver)
    finish_rel_branch(relver)
    publish(pypi_index)