What is the difference between <class 'str'> and <type 'str'>

dom free picture dom free · Feb 5, 2017 · Viewed 34.8k times · Source

I am new to python. I'm confused by the <class 'str'>. I got a str by using:

response = urllib.request.urlopen(req).read().decode()

The type of 'response' is <class 'str'>, not <type 'str'>. When I try to manipulate this str in 'for loop':

for ID in response: 

The 'response' is read NOT by line, BUT by character. I intend to put every line of 'response' into individual element of a list. Now I have to write the response in a file and use 'open' to get a string of <type 'str'> that I can use in 'for loop'.

Answer

tdelaney picture tdelaney · Feb 5, 2017

There is no difference. Python changed the text representation of type objects between python 2 (Types are written like this: <type 'int'>.) and python 3 (Types are written like this: <class 'int'>.). In both python 2 and 3, the type of the type object is, um, type:

python 2

>>> type(type('a'))
<type 'type'>

python 3

>>> type(type('a'))
<class 'type'>

And that's the reason for the change... the string representation makes it clear that the type is a class.

As for the rest of your problem,

for ID in response:

response is a string and enumerating it gives the characters in the string. Depending on the type of response you may want to use and HTML, JSON or other parser to turn it into python objects.