[Python] Pickling error with multiprocessing module in a unittest, but not via regular python.

I am getting this error inside a unittest while using the multiprocessing package.
PicklingError: Can't pickle <type 'function'>: attribute lookup __builtin__.function failed

Running the following code works inside of a regular python file but when put into a unittest, it raises the pickling error as I posted above. This is the simplest example I could spin up.

# The following, works.
import multiprocessing

def hello(number):
print "hello"

number_processes = 2
pool = multiprocessing.Pool(number_processes)
total_tasks = 2
tasks = range(total_tasks)
results = pool.map(hello, tasks)
pool.close()
pool.join()


Next code block:

# This does not work, i'm running it via unittest runner
import multiprocessing
import unittest
class Testing123(unittest.TestCase):
test_1(self):

def hello(number):
print "hello"

number_processes = 2
pool = multiprocessing.Pool(number_processes)
total_tasks = 2
tasks = range(total_tasks)
results = pool.map(hello, tasks)
pool.close()
pool.join()

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