[python] Key error when selecting columns in pandas dataframe after read_csv

I'm trying to read in a CSV file into a pandas dataframe and select a column, but keep getting a key error.

The file reads in successfully and I can view the dataframe in an iPython notebook, but when I want to select a column any other than the first one, it throws a key error.

I am using this code:

import pandas as pd

transactions = pd.read_csv('transactions.csv',low_memory=False, delimiter=',', header=0, encoding='ascii')
transactions['quarter']

This is the file I'm working on: https://www.dropbox.com/s/81iwm4f2hsohsq3/transactions.csv?dl=0

Thank you!

The key error generally comes if the key doesn't match any of the dataframe column name 'exactly':

You could also try:

import csv
import pandas as pd
import re
    with open (filename, "r") as file:
        df = pd.read_csv(file, delimiter = ",")
        df.columns = ((df.columns.str).replace("^ ","")).str.replace(" $","")
        print(df.columns)

if you need to select multiple columns from dataframe use 2 pairs of square brackets eg.

df[["product_id","customer_id","store_id"]]