Unlike text documents, which Python has a native open() function for:

Python: How to open and read text documents

Opening and reading .csv files requires importing the csv module and using a csv.reader(). For example, this code will open and read the first 10 lines in a .csv file:

import csv

csv_path = r'C:\Users\Chris\Desktop\Python Scripts\Python Class\Week_2\code examples\EEU_071114.csv'

reader = csv.reader(open(csv_path, 'r'), dialect='excel-tab')

# Print only the first 10 lines
x = 0
for line in reader:
    print line
    x += 1
    if x > 10:
        break

Output:

['Czech Republic,Czech (CZE),Street Names,"43,585"']
[',,Zones,160']
[',,Admins,"10,349"']
[',,Signs,"5,520"']
[',,POI Names,"72,297"']
['Greece,Greek (GRE),Street Names,"41,138"']
[',,Zones,"1,199"']
[',,Admins,"3,916"']
[',,Signs,"7,009"']
[',,POI Names,"60,878"']
['Hungary,Hungarian (HUN),Street Names,"33,926"']

 

Notice this key line:

reader = csv.reader(open(csv_path, 'r'), dialect='excel-tab')

The first argument to csv.reader() is open(csv_path, 'r') . Just like opening text documents, use open(), with an ‘r’ argument for ‘read’. The second argument is dialect='excel-tab' .

reader is a csv read object that is iterable, but not accessible by index, so if we want to capture all lines of the csv file in a list, we must first iterate over the reader object. For example:

import csv

csv_path = r'C:\Users\Chris\Desktop\Python Scripts\Python Class\Week_2\code examples\EEU_071114.csv'

reader = csv.reader(open(csv_path, 'r'), dialect='excel-tab')

# Capture all lines in an array
csv_doc = []
for line in reader:
    csv_doc.append(line)

Then if we wanted to print the last line of the csv file we could do so by index:

# Print the last line of the csv document
print csv_doc[-1]

which yields:

[',,POI Names,"22,450"']

Notice that the line is returned as a comma separated string in an array. We can now parse this data by splitting the string by comma. For example:

# For the first 5 lines, split each line by comma
x = 0
for line in reader:
    line = line[0]
    line = line.split(',')
    print line
    x += 1
    if x > 5:
        break

which yields:

['Czech Republic', 'Czech (CZE)', 'Street Names', '"43', '585"']
['', '', 'Zones', '160']
['', '', 'Admins', '"10', '349"']
['', '', 'Signs', '"5', '520"']
['', '', 'POI Names', '"72', '297"']
['Greece', 'Greek (GRE)', 'Street Names', '"41', '138"']

 
For more information about the csv module, see:
https://docs.python.org/2/library/csv.html