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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 projects(accountable):
 """ List all projects. """

    projects = accountable.metadata()['projects']
    headers = sorted(['id', 'key', 'self'])
    rows = [[v for k, v in sorted(p.items()) if k in headers] for p in projects]
    rows.insert(0, headers)
    print_table(SingleTable(rows))