Reading from CSV files

Let's discuss an example where we read the contents of the CSV file created in the previous section:

1. The first step in reading a CSV file is opening it in read mode:

       with open("csv_example.csv", 'r') as csv_file:

2. Next, we initialize an instance of the reader class from the CSV module. The contents of the CSV file are loaded into the object csv_reader:

       csv_reader = csv.reader(csv_file)

3. Now that the contents of the CSV file are loaded, each row of the CSV file could be retrieved as follows:

       for row in csv_reader: 
           print(row)

4. Put it all together:

       import csv 

       if __name__ == "__main__": 
          # initialize csv writer 
          with open("csv_example.csv", 'r') as csv_file: 
                csv_reader = csv.reader(csv_file) 

                for row in csv_reader: 
                      print(row)

5. When the preceding code snippet is executed (available for download along with this chapter as csv_read.py), the contents of the file are printed row-by-row where each row is a list that contains the comma separated values:

       ['123', '456', '789']
       ['Red', 'Green', 'Blue']