Question

I’m trying to learn the classes in python:

#!/usr/bin/env python
# *-* coding: utf-8 *-*

import urllib2
from BeautifulSoup import BeautifulSoup as bs

class Crawler:

    def visit(self, url):
        self.request = urllib2.Request(self.url)
        self.response = urllib2.urlopen(self.request)
        return self.response.read()

if __name__ == "__main__":
    x = Crawler()
    print x.visit("http://google.com/")

When I try to start getting the error:

sigo@sarch ~/sources $ python test.py 
Traceback (most recent call last):
  File "test.py", line 16, in <module>
    print x.visit("http://google.com/")
  File "test.py", line 10, in visit
    self.request = urllib2.Request(self.url)
AttributeError: Crawler instance has no attribute 'url'

What am I doing wrong?

Answer 1

You’re saying self.url which is referring to the Crawler class’s url attribute, which does not exist. You need to use just url since that’s the name of the variable from your visit() function arguments.