for row in df.CUSTOMER_CONTENTION_TEXT.values: Where can i find it with my excel file

import matplotlib.pyplot as plt
import pandas as pd
plt.style.use('ggplot')

from wordcloud import WordCloud, STOPWORDS

df = pd.read_excel(r'crawling.xlsx')

text = ''
for row in df.CUSTOMER_CONTENTION_TEXT.values:
    text = text + row.value() + ' '

wc = WordCloud(max_words=2000,
               stopwords=STOPWORDS, font_path=r'NanumBarunGothic.otf')
# generate word cloud
wc.generate(text)

# store to file
wc.to_file(r'first.png')

# show
plt.imshow(wc)
plt.axis("off")
plt.figure()
plt.axis("off")
plt.show()

I got a code from github [https://gist.github.com/pybokeh/de5475328fb2bbb33cb7] python_wordcloud_from_excel.ipynb

for row in df.CUSTOMER_CONTENTION_TEXT.values:

I can not understand. Can you explain this? I want to fix this code and use it, but I don't know how to fix this.