Code no longer working

[yk303]

Everyone,

I want to move this thread forward. bowlofred pointed me in the right direction with my problem.

I now have another problem my code. Can you please have a look. I am pasting the code again and the error I am receiving.

#Very good file. Third revision!
import os
import pandas as pd
pd.set_option('display.max_rows', 500)
import itertools
import datetime as dt
from matplotlib import pyplot as plt
import matplotlib as mpl
mpl.use('Agg')
import numpy as np
import matplotlib.pyplot as plt
#%matplotlib inline
#from IPython import get_ipython
#get_ipython().run_line_magic('matplotlib', 'inline')
import seaborn as sns

import re

from collections import Counter

import string
import emoji

import pickle
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.dates as mdates
import matplotlib.cbook as cbook

import pandas as pd 
import time
import sys
from wordcloud import WordCloud, STOPWORDS
from PIL import Image

files_groups = os.listdir('data/')
def read_history(file,conv_type):
    f = open('data/{}/{}'.format(conv_type,file), 'r',)
 
    # Feed the file text into findall(); it returns a list of all the found strings
    messages = re.findall('\[(\d+-\d+-\d+, \d+:\d+:\d+ [A-Z]*)\] (.*?): (.*)', f.read())
    f.close()

    
    #Convert list to a dataframe and name columns
    history = pd.DataFrame(messages,columns =['date','name','msg'])
    history['date'] = pd.to_datetime(history['date'],format="%Y-%m-%d, %I:%M:%S %p")
    history['date1'] = history['date'].apply(lambda x: x.date())
    history['msg_len'] = history['msg'].str.len()
    history['conv_name'] = file[19:-4]
    history['conv_name'] = file[19:-4]
# Get Media shared in the Message
    history['Media']=history['msg'].str.contains('omitted')
    return history
history['Media']
all = []

for file in files_groups:
    history = read_history(file,'')
    history['tipo'] = 'g'
    all.append(history)
    history = pd.concat(all).reset_index()
    history_clean = history[history['msg']!=' <Media omitted>'].sort_values(by=['conv_name','name','date1'])
history_clean.shape
history.columns

Error:
Matplotlib created a temporary config/cache directory at /tmp/matplotlib-4oa8sevy because the default path (/config/matplotlib) is not a writable directory; it is highly recommended to set the MPLCONFIGDIR environment variable to a writable directory, in particular to speed up the import of Matplotlib and to better support multiprocessing.
Traceback (most recent call last):
  File "main.py", line 55, in <module>
    history['Media']
NameError: name 'history' is not defined
 

Please note, I have a folder called Data in Repl that I have created. Inside this folder is the text file that contains the whatsapp chat data.

Thank you in advance.

YK