Urllib2 in Python 3

1. the urllib in Python 3
2. Understand the Root Cause of the ModuleNotFoundError: No module named 'urllib2' in Python
3. Replicate the ModuleNotFoundError: No module named 'urllib2' in Python
4. Solve the ModuleNotFoundError: No module named 'urllib2' in Python

In this tutorial, we aim to explore methods to solve the issue of ModuleNotFoundError: No module named 'urllib2' in Python.

the urllib in Python 3

The Python module for processing URLs is called the urllib package. URLs can be fetched with it, and it can fetch URLs using various protocols and the urlopen method.

Some other methods associated with the urllib package are:

1. urllib.parse - This method is mainly used to parse the data within a particular URL.
2. urllib.request - This method is mainly used to request and process the URL passed as a parameter.
3. urllib.robotparser - This method parses robot.txt types of files.
4. urllib.error - This method is mainly used to identify any errors raised while using the urllib.request function.

Understand the Root Cause of the ModuleNotFoundError: No module named 'urllib2' in Python

The error message most generally faced when it comes to urllib2 in Python 3 is the ModuleNotFoundError. This error is mainly because the urllib2 is no longer supported in Python 3.

According to the urllib2 documentation, the urllib2 module has been split across several modules in Python 3 named urllib.request and urllib.error. Now let us understand how to replicate this issue.

Replicate the ModuleNotFoundError: No module named 'urllib2' in Python

The above issue can be illustrated with the help of the following block of code.

import urllib2

Output:

ModuleNotFoundError: No module named 'urllib2'

Another scenario that produces the error is using the urlopen function within the urllib2 package. This function has been moved to a new place called request within the package in Python 3.

This problem can be replicated with the help of the following block of code.

import urllib2.request

response = urllib2.urlopen("http://www.google.com")
html = response.read()
print(html)

The output of the above code can be illustrated as follows.

ModuleNotFoundError: No module named 'urllib2'

Now that we have seen how to replicate the issue let us try to correct it.

Solve the ModuleNotFoundError: No module named 'urllib2' in Python

To solve the error, we need some changes to the code above.

1. Use urllib.request instead of urllib2.
2. Use urlopen("http://www.google.com/") instead of urllib2.urlopen("http://www.google.com").

The above changes are implemented with the help of the following block of code.

from urllib.request import urlopen

html = urlopen("http://www.google.com/").read()
print(html)

The above code would successfully read out the elements of the page http://www.google.com/.

Thus, we have successfully solved the problem associated with urllib2 in Python 3.