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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 email_message(self):
 """ compose complete email message text """

        url = settings.SITE_URL
        hello_text = __("Hi %s," % self.to_user.get_full_name())
        action_text = __("\n\nMore details here: %s") % url
        explain_text = __(
            "This is an automatic notification sent from from %s.\n"
            "If you want to stop receiving this notification edit your"
            "email notification settings here: %s") % (settings.SITE_NAME, 'TODO')

        return "%s\n\n%s%s\n\n%s" % (hello_text, self.text, action_text, explain_text)