How To Fix Python Error TypeError: ‘str’ Object Is Not Callable

This article summarizes several cases that will throw Python TypeError: ‘str’ object is not callable, it will also tell you how to fix the error in each case.

1. Define str As A Python Variable.

1.1 How To ReProduce Python Error TypeError: ‘str’ Object Is Not Callable.

When I develop a python program, I want to use the Python built-in function str() to convert a number variable to string type. But I meet below error Typeerror: ‘str’ Object Is Not Callable. 

>>> x = 1.99
>>>
>>> str(x)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'str' object is not callable

This error confused me a lot for some time. But I finally fix it after googling it. The reason for this error is because I use a variable name str in the same python interpreter, and I had assign a string value to that variable str. So the python interpreter treats str as a variable name other than the built-in function name str(). So it throws out TypeError: ‘str’ object is not callable. Below is the full python source code.

>>> global str
>>>
# some times ago, I assign string 'hello' to str variable, so python interpreter think str is a string variable.
>>> str = 'hello'
>>>
......
......
......
>>> x= 1.99
# so when I invoke str() function, the interpreter think str is a string variable then below error is thrown.
>>> str(x)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'str' object is not callable

1.2 How To Fix Python Error TypeError: ‘str’ Object Is Not Callable.

1. It is very easy to fix this error.
2. Run del str command to delete the variable.
3. After that, you can call str() funcion as normal.

   >>> global str
   >>> 
   >>> str = 'hello'
   >>> 
   >>> x = 1.99
   >>> 
   >>> str(x)
   Traceback (most recent call last):
     File "<stdin>", line 1, in <module>
   TypeError: 'str' object is not callable
   >>> 
   >>> del str
   >>> 
   >>> str(x)
   '1.99'

1.3 Conclusion.

Do not declare python variable name as same with python built-in function name or keyword etc.

2. Use A Python String As A Function Name.

2.1 Reproduce.

In this case, it uses the python easygui module to get an integer number from user input, and then calculate the number as a percentage number. Please see below source code.

# Import all functions from easygui module.
from easygui import *


def easygui_str_type_error():
    
    # Prompt a GUI dialog to gather user input integer number.
    number_str = enterbox("Please input an integer number as percentage.")
    
    # Convert the string number to integer value.
    number_int = int(number_str)
    
    if number_int > 100:
        
        msgbox("The input number is bigger than 100, it is invalid.")
    
    else:
        # Display a GUI dialog to show the percentage.
        msgbox("The percentage is "(number_int * 0.01))
        


if __name__ == '__main__':
    
    easygui_str_type_error()

When you run the above python code, it will throw below error message.

Traceback (most recent call last):
  File "/string/PythonStrTypeError.py", line 31, in <module>
    easygui_str_type_error()
  File "/string/PythonStrTypeError.py", line 23, in easygui_str_type_error
    msgbox("The percentage is "(number_int * 0.01))
TypeError: 'str' object is not callable

2.2 How To Fix.

1. The error occurs at the code line msgbox("The percentage is "(number_int * 0.01)).
2. This is because there is nothing between the string literal (“The percentage is “) and the (number_int * 0.01) parenthesis.
3. So Python interpreter treats the string “The percentage is ” as an invokable object ( a function name ), but the code real purpose is to splice two string.
4. So we can change the code to msgbox("The percentage is " + str(number_int * 0.01)) to fix the error.
5. We can also use string formatting in a more regular way.

   msgbox("The percentage is {} ".format(number_int * 0.01))