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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 switch_lang(self):
 """Switch to the language of the current user. If the current language is already the specified one, nothing will be done. """

        locale = self.current.locale
        translation.InstalledLocale.install_language(locale['locale_language'])
        translation.InstalledLocale.install_locale(locale['locale_datetime'], 'datetime')
        translation.InstalledLocale.install_locale(locale['locale_number'], 'number')