'Retrive all variable data and update hmvariable states.'

def _update_variables(self, now):

    variables = self._homematic.getAllSystemVariables(self._name)
    if (variables is None):
        return
    state_change = False
    for (key, value) in variables.items():
        if ((key in self._variables) and (value == self._variables[key])):
            continue
        state_change = True
        self._variables.update({key: value})
    if state_change:
        self.schedule_update_ha_state()
