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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_sms_with_callback_token(user, mobile_token, **kwargs):
 """ Sends a SMS to user.mobile via Twilio. Passes silently without sending in test environment. """

    base_string = kwargs.get('mobile_message', api_settings.PASSWORDLESS_MOBILE_MESSAGE)

    try:

        if api_settings.PASSWORDLESS_MOBILE_NOREPLY_NUMBER:
            # We need a sending number to send properly
            if api_settings.PASSWORDLESS_TEST_SUPPRESSION is True:
                # we assume success to prevent spamming SMS during testing.
                return True

            from twilio.rest import Client
            twilio_client = Client(os.environ['TWILIO_ACCOUNT_SID'], os.environ['TWILIO_AUTH_TOKEN'])
            twilio_client.messages.create(
                body=base_string % mobile_token.key,
                to=getattr(user, api_settings.PASSWORDLESS_USER_MOBILE_FIELD_NAME),
                from_=api_settings.PASSWORDLESS_MOBILE_NOREPLY_NUMBER
            )
            return True
        else:
            logger.debug("Failed to send token sms. Missing PASSWORDLESS_MOBILE_NOREPLY_NUMBER.")
            return False
    except ImportError:
        logger.debug("Couldn't import Twilio client. Is twilio installed?")
        return False
    except KeyError:
        logger.debug("Couldn't send SMS."
                  "Did you set your Twilio account tokens and specify a PASSWORDLESS_MOBILE_NOREPLY_NUMBER?")
    except Exception as e:
        logger.debug("Failed to send token SMS to user: {}. "
                  "Possibly no mobile number on user object or the twilio package isn't set up yet. "
                  "Number entered was {}".format(user.id, getattr(user, api_settings.PASSWORDLESS_USER_MOBILE_FIELD_NAME)))
        logger.debug(e)
        return False