def check_positive(number, var_name):
	pass

def check_not_empty(var, var_name):
	pass

def check_callback(callback, num_args_desired, callback_name = 'callback'):
	pass

def check_sensors_paths(sensors_paths):
	pass

def check_types():
	pass

def check_list_types(list_obj, cls):
	pass

class SingletonMeta(type):


class OneElementQueue(asyncio.Queue):


    def push(self, item):
    	pass

    def is_full(self):
    	pass

    def clean(self):
    	pass

