'Access the extensions
:returns: twilio.rest.preview.marketplace.available_add_on.available_add_on_extension.AvailableAddOnExtensionList
:rtype: twilio.rest.preview.marketplace.available_add_on.available_add_on_extension.AvailableAddOnExtensionList'

@property
def extensions(self):

    if (self._extensions is None):
        self._extensions = AvailableAddOnExtensionList(self._version, available_add_on_sid=self._solution['sid'])
    return self._extensions
