A syntax error occurred in the tutorial

[zhouhao-learning]

Hello, I recently paid attention to your part of this tutorial, but I encountered source code problems when implementing your tutorial, when I executed

from ktext.preprocess import processor
body_pp = processor(keep_n=8000, padding_maxlen=70)
train_body_vecs = body_pp.fit_transform(train_body_raw)

I got the following error:

OSError                                   Traceback (most recent call last)
~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/ktext/preprocess.py in apply_parallel(func, data, cpu_cores)
     72         chunk_size = ceil(len(data) / cpu_cores)
---> 73         pool = Pool(cpu_cores)
     74         transformed_data = pool.map(func, chunked(data, chunk_size), chunksize=1)

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/multiprocess/pool.py in __init__(self, processes, initializer, initargs, maxtasksperchild, context)
    173         self._pool = []
--> 174         self._repopulate_pool()
    175 

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/multiprocess/pool.py in _repopulate_pool(self)
    238             w.daemon = True
--> 239             w.start()
    240             util.debug('added worker')

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/multiprocess/process.py in start(self)
    104         _cleanup()
--> 105         self._popen = self._Popen(self)
    106         self._sentinel = self._popen.sentinel

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/multiprocess/context.py in _Popen(process_obj)
    276             from .popen_fork import Popen
--> 277             return Popen(process_obj)
    278 

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/multiprocess/popen_fork.py in __init__(self, process_obj)
     18         self.returncode = None
---> 19         self._launch(process_obj)
     20 

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/multiprocess/popen_fork.py in _launch(self, process_obj)
     65         parent_r, child_w = os.pipe()
---> 66         self.pid = os.fork()
     67         if self.pid == 0:

OSError: [Errno 12] Cannot allocate memory

During handling of the above exception, another exception occurred:

UnboundLocalError                         Traceback (most recent call last)
<timed exec> in <module>()

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/ktext/preprocess.py in fit_transform(self, data)
    336 
    337         """
--> 338         tokenized_data = self.fit(data, return_tokenized_data=True)
    339 
    340         logging.warning(f'...fit is finished, beginning transform')

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/ktext/preprocess.py in fit(self, data, return_tokenized_data)
    278         now = get_time()
    279         logging.warning(f'....tokenizing data')
--> 280         tokenized_data = self.parallel_process_text(data)
    281 
    282         if not self.padding_maxlen:

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/ktext/preprocess.py in parallel_process_text(self, data)
    233                                                 end_tok=self.end_tok)
    234         n_cores = self.num_cores
--> 235         return flattenlist(apply_parallel(process_text, data, n_cores))
    236 
    237     def generate_doc_length_stats(self):

~/anaconda3/envs/deep2.0.0/lib/python3.6/site-packages/ktext/preprocess.py in apply_parallel(func, data, cpu_cores)
     74         transformed_data = pool.map(func, chunked(data, chunk_size), chunksize=1)
     75     finally:
---> 76         pool.close()
     77         pool.join()
     78         return transformed_data

UnboundLocalError: local variable 'pool' referenced before assignment

This error seems to be due to an error caused by your source code. Can you see what happened?