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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 addcomment(accountable, body):
 """ Add a comment to the given issue key. Accepts a body argument to be used as the comment's body. """


    r = accountable.issue_add_comment(body)
    headers = sorted(['author_name', 'body', 'updated'])
    rows = [[v for k, v in sorted(r.items()) if k in headers]]
    rows.insert(0, headers)
    print_table(SingleTable(rows))