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Importing text files line by line

For large files, we may not want to print all of their content to the shell: you may wish to print only the first few lines. Enter the .readline() method, which allows you to do this. When a file called file is open, you can print out the first line by executing file.readline(). If you execute the same command again, the second line will print, and so on.

In the introductory video, Hugo also introduced the concept of a context manager. He showed that you can bind a variable file by using a context manager construct:

with open('huck_finn.txt') as file:

While still within this construct, the variable file will be bound to open('huck_finn.txt'); thus, to print the file to the shell, all the code you need to execute is:

with open('huck_finn.txt') as file:
    print(file.readline())

You'll now use these tools to print the first few lines of moby_dick.txt!

Bu egzersiz

Introduction to Importing Data in Python

kursunun bir parçasıdır
Kursu Görüntüle

Egzersiz talimatları

  • Open moby_dick.txt using the with context manager and the variable file.
  • Print the first three lines of the file to the shell by using .readline() three times within the context manager.

Uygulamalı interaktif egzersiz

Bu örnek kodu tamamlayarak bu egzersizi bitirin.

# Read & print the first 3 lines
with open('moby_dick.txt') as ____:
    print(____)
    print(____)
    print(____)
Kodu Düzenle ve Çalıştır