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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 beacon(config):
    '''
    Emit a dict name "texts" whose value is a list
    of texts.

    .. code-block:: yaml

        beacons:
          twilio_txt_msg:
            - account_sid: "<account sid>"
            - auth_token: "<auth token>"
            - twilio_number: "+15555555555"
            - interval: 10

    '''
    log.trace('twilio_txt_msg beacon starting')

    _config = {}
    list(map(_config.update, config))

    ret = []
    if not all([_config['account_sid'],
                _config['auth_token'],
                _config['twilio_number']]):
        return ret
    output = {}
    output['texts'] = []
    client = TwilioRestClient(_config['account_sid'], _config['auth_token'])
    messages = client.messages.list(to=_config['twilio_number'])
    num_messages = len(messages)
    log.trace('Num messages: %d', num_messages)
    if not num_messages:
        log.trace('Twilio beacon has no texts')
        return ret

    for message in messages:
        item = {}
        item['id'] = six.text_type(message.sid)
        item['body'] = six.text_type(message.body)
        item['from'] = six.text_type(message.from_)
        item['sent'] = six.text_type(message.date_sent)
        item['images'] = []

        if int(message.num_media):
            media = client.media(message.sid).list()
            if media:
                for pic in media:
                    item['images'].append(six.text_type(pic.uri))
        output['texts'].append(item)
        message.delete()
    ret.append(output)
    return ret