Google colab GPU环境下导包报错

RuntimeError Traceback (most recent call last)
in ()
----> 1 from sko.PSO import PSO
2 from sko.GA import GA

4 frames
/usr/local/lib/python3.7/dist-packages/sko/__init__.py in ()
1 __version__ = '0.6.5'
2
----> 3 from . import DE, GA, PSO, SA, ACA, AFSA, IA, tools
4
5

/usr/local/lib/python3.7/dist-packages/sko/DE.py in ()
9 from abc import ABCMeta, abstractmethod
10 from .operators import crossover, mutation, ranking, selection
---> 11 from .GA import GeneticAlgorithmBase, GA
12
13

/usr/local/lib/python3.7/dist-packages/sko/GA.py in ()
7 import numpy as np
8 from .base import SkoBase
----> 9 from sko.tools import func_transformer
10 from abc import ABCMeta, abstractmethod
11 from .operators import crossover, mutation, ranking, selection

/usr/local/lib/python3.7/dist-packages/sko/tools.py in ()
7
8 if sys.platform != 'win32':
----> 9 multiprocessing.set_start_method('fork')
10
11

/usr/lib/python3.7/multiprocessing/context.py in set_start_method(self, method, force)
240 def set_start_method(self, method, force=False):
241 if self._actual_context is not None and not force:
--> 242 raise RuntimeError('context has already been set')
243 if method is None and force:
244 self._actual_context = None

RuntimeError: context has already been set