<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def activate(locale, path=None):
 """Set 'locale' as current locale. Search for locale in directory 'path' @param locale: language name, eg 'en_GB'"""

    if path is None:
        path = _DEFAULT_LOCALE_PATH
    if locale not in _TRANSLATIONS:
        translation = gettext_module.translation('humanize', path, [locale])
        _TRANSLATIONS[locale] = translation
    _CURRENT.locale = locale
    return _TRANSLATIONS[locale]