I am trying to use the multiprocessing map function to execute a function over my list. However in this function I do some API calls which can not be executed at the same time since it will overload the API. However my code is spread out over multiple files since it is quite long. I have tried to follow to follow this solution however it does not work for me. I suspect it does not work because I am working with more than one file. The specific error I get is: NameError: name 'lock' is not defined. Hereby a simplyfication of my code: main.py import file2 def evaluate_entry_of_list(entry): response = file2.get_data(entry) # some calculations return results def init_pool(given_lock): global lock lock = given_lock if __name__ == '__main__': list = apicaller.get_list() t_lock = Lock() with Pool(8, initializer=init_pool, initargs=(t_lock,)) as pool: results = pool.map(evaluate_entry_of_list, list) process_results(results) file2.py def make_call(url, body)-> requests.Response: lock.acquire() # Make API call lock.release() return response Other solutions I tried: defining a variable in main and import to file2 and use separate class to create static variable and import in file2. Continue reading...