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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 update_password_from_form(self, user=None, form=None):
 """Updates the user password using a form """

        user = user or self.current
        if not form and "form" in current_context.data and request.method == "POST":
            form = current_context.data.form
        elif not form:
            raise OptionMissingError("Missing a form in 'update_user_password' action")

        self._update_password_from_form(user, form)
        save_model(user)
        self.update_user_password_signal.send(self, user=user)