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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 commit(using=None):
 """ Does the commit itself and resets the dirty flag. """

    if using is None:
        for using in tldap.backend.connections:
            connection = tldap.backend.connections[using]
            connection.commit()
        return
    connection = tldap.backend.connections[using]
    connection.commit()