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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 pending():
 """Show the number of pending signals by signal type."""


    signalbus = current_app.extensions['signalbus']
    pending = []
    total_pending = 0
    for signal_model in signalbus.get_signal_models():
        count = signal_model.query.count()
        if count > 0:
            pending.append((count, signal_model.__name__))
        total_pending += count
    if pending:
        pending.sort()
        max_chars = len(str(pending[-1][0]))
        for n, signal_name in pending:
            click.echo('{} of type "{}"'.format(str(n).rjust(max_chars), signal_name))
    click.echo(25 * '-')
    click.echo('Total pending: {} '.format(total_pending))