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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 start(name):
 # type: (str) -> None """ Start working on a new hotfix. This will create a new branch off master called hotfix/<name>. Args: name (str):
 The name of the new feature. """

    hotfix_branch = 'hotfix/' + common.to_branch_name(name)
    master = conf.get('git.master_branch', 'master')

    common.assert_on_branch(master)
    common.git_checkout(hotfix_branch, create=True)