AttributeError: Can‘t get attribute ‘guess_gender‘ on ＜module ‘__main__‘ (built-in)＞

问题描述：

AttributeError: Can’t get attribute ‘guess_gender’ on <module ‘main’ (built-in)>

---

原始代码：

import sys
import gender_guesser.detector as gender
import multiprocessing
import time

d = gender.Detector()

def guess_gender (name):
    n = name.title() # make first letter upper case and the rest lower case 
    g = d.get_gender(n) # guess gender
    return g

ls = ['john','joe','amamda','derick','peter','ashley','john','joe','amamda','derick','peter','ashley']

t=time.time()

results=[]
def callBack(x):
    results.append(x)

pool = multiprocessing.Pool(processes=multiprocessing.cpu_count()-1, maxtasksperchild=1)

for n in ls:
    print (n)
    pool.apply_async(guess_gender,args=[n],callback=callBack)

pool.close()
pool.join()

results = pd.concat(results)

print(time.time()-t)

解决方案：

将f()函数放到另一个py文件中，通过模块引用调用它
f.py如下

def f(name, output):
  output.put('hello {0}'.format(name))
  return

main.py如下

from multiprocessing import Process, Queue

#Having the function definition here results in
#AttributeError: Can't get attribute 'f' on <module '__main__' (built-in)>

#The solution seems to be importing the function from a separate file.

import f

#Also, the original version of f only had a print statement in it.  
#That doesn't work with Process - in the sense that it prints to the console 
#instead of the notebook.
#The trick is to let f write the string to print into an output-queue.
#When Process is done, the result is retrieved from the queue and printed.

if __name__ == '__main__':    

   # Define an output queue
   output=Queue()

   # Setup a list of processes that we want to run
   p = Process(target=f.f, args=('Bob',output))

   # Run process
   p.start()

   # Exit the completed process
   p.join()

   # Get process results from the output queue
   result = output.get(p)

   print(result)