How to use the gaiatest.apps.keyboard.app.Keyboard function in gaiatest

def tap_submit(self):
        el = self.marionette.find_element(*self._submit_locator)
        from gaiatest.apps.keyboard.app import Keyboard
        k = Keyboard(self.marionette)
        # The keyboard can overlay the submit button on desktop b2g, so close it
        k.dismiss()
        self.marionette.find_element(*self._submit_locator).tap()

def tap_submit(self):
        el = self.marionette.find_element(*self._submit_locator)
        from gaiatest.apps.keyboard.app import Keyboard
        k = Keyboard(self.marionette)
        # The keyboard can overlay the submit button on desktop b2g, so close it
        k.dismiss()
        self.marionette.find_element(*self._submit_locator).tap()

def keyboard(self):
        from gaiatest.apps.keyboard.app import Keyboard
        return Keyboard(self.marionette)

def tap_number_input(self):
        number_input = self.marionette.find_element(*self._number_input_locator)
        self.marionette.execute_script("arguments[0].scrollIntoView(false);", [number_input])
        number_input.tap()
        from gaiatest.apps.keyboard.app import Keyboard

        return Keyboard(self.marionette)

def tap_email_input(self):
        self.marionette.find_element(*self._email_input_locator).tap()
        from gaiatest.apps.keyboard.app import Keyboard

        return Keyboard(self.marionette)

def tap_url_input(self):
        self.marionette.find_element(*self._url_input_locator).tap()
        from gaiatest.apps.keyboard.app import Keyboard

        return Keyboard(self.marionette)

def tap_text_input(self):
        self.marionette.find_element(*self._text_input_locator).tap()
        from gaiatest.apps.keyboard.app import Keyboard

        return Keyboard(self.marionette)

def tap_recipient_section(self):
        self.marionette.find_element(*self._recipient_section_locator).tap()
        from gaiatest.apps.keyboard.app import Keyboard
        return Keyboard(self.marionette)