Difficulty in understanding the error in python

Question

I wrote a piece of code in python that reads a string, split it into 2 parts,the first being a string again and the second being an integer. For example

ABDKEK 1255443

The code is as follows:

 L=raw_input()
 ls=L.split()
 num=int(ls[1])
 L=ls[0]
 len=len(L)

and it gives the following error

 len=len(L) 
TypeError: 'int' object is not callable

I make the following change in the code:

 length=len(L)

and it works.

Can anyone explain what does the error 'int' object is not callable mean??

• Tim Peters: Don't use len as a variable name. If you do, you'll no longer be able to access the builtin function named len. Note that you'll get the same error from, e.g., 3(2). An int cannot be called.
• alphacentauri: Yeah..got it..I had also declared the variable len=0 at the beginning. When I removed it, even len=len(L) works, but then if I try to use len(L) one more time, it gives an error, coz now len is a variable and no longer a built in function. Thanks!!
• Tim Peters: Yup, you got it! Good work :-)

Answer 1

len is a function name which is already defined and should not be use as a variable. Try some other name instead.

• alphacentauri: Thanks.... but I was asking the interpretation of the error.. as in..why the word 'int' was used.