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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 checkout(accountable, issue_key):
 """ Checkout a new branch or checkout to a branch for a given issue. """

    issue = accountable.checkout(issue_key)
    headers = issue.keys()
    rows = [headers, [v for k, v in issue.items()]]
    print_table(SingleTable(rows))