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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 event_return(events):
    '''
    Send the events to a mattermost room.

    :param events:      List of events
    :return:            Boolean if messages were sent successfully.
    '''
    _options = _get_options()

    api_url = _options.get('api_url')
    channel = _options.get('channel')
    username = _options.get('username')
    hook = _options.get('hook')

    is_ok = True
    for event in events:
        log.debug('Event: %s', event)
        log.debug('Event data: %s', event['data'])
        message = 'tag: {0}\r\n'.format(event['tag'])
        for key, value in six.iteritems(event['data']):
            message += '{0}: {1}\r\n'.format(key, value)
        result = post_message(channel,
                              message,
                              username,
                              api_url,
                              hook)
        if not result:
            is_ok = False

    return is_ok