Import Python multiprocessing main function in another Python file as a module -

i physicist , new python migrated matlab. need implement multiprocessing perform calculations genetic optimization algorithm.

i have managed make multiprocessing work in single python file using information found on-line. example code created replicate problem (it doesn't useful).

import numpy np import multiprocessing mp      def fun1((index, array)):      lst_1=[]     ar_i in array:         lst_1.append(ar_i+index)      return np.sum(np.squeeze(lst_1))          def main(n):     arr=np.arange(1,n)      lst=[]     elem in arr:                 lst.append((elem,arr))       p = mp.pool(8)     a=p.map(fun1, lst)          return           if __name__ == "__main__":     ans=main(30)  

if run python console gives me answer. python console can import function python file , works. example:

import example1 ans2=example1.main(20) 

but if in python file (for example main genetic algorithm file) , import function again , try run as:

import example1 ans3=example1.main(10) 

i error message:

"runtimeerror:              attempt start new process before current process             has finished bootstrapping phase.              means on windows , have             forgotten use proper idiom in main module:                  if __name__ == '__main__':                     freeze_support()                     ...              "freeze_support()" line can omitted if program             not going frozen produce windows executable." 

how can solve problem? searched online haven't been able figure out. perhaps missing obvious. thank you.