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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 send_message(frm=None, to=None, text=None):
 """Shortcut to send a sms using libnexmo api. :param frm: The originator of the message :param to: The message's recipient :param text: The text message body Example usage: """

    assert to is not None
    assert text is not None

    if frm is None:
        frm = settings.NEXMO_DEFAULT_FROM

    client = nexmo.Client(key=settings.NEXMO_API_KEY, secret=settings.NEXMO_API_SECRET)
    response = client.send_message({
        'from': frm,
        'to': to,
        'text': text
    })
    return response