Why am I getting a \'NameError: name is not defined\' in my Python script?

Python NameError: Resolving Name Definition Issues

When executing a Python script, you may encounter the error "NameError: name is not defined." This error signifies that the script cannot locate the specified name or identifier within the program's namespace. Let's explore the root cause of this error and identify its solution.

The given code snippet illustrates this issue:

s = Something()
s.out()

class Something:
    def out(self):
        print("it works")

Upon running this script, the interpreter encounters the "NameError: name 'Something' is not defined" exception. This is because the class Something is not defined before it is instantiated as an object. To resolve this issue, the class definition must precede its usage:

class Something:
    def out(self):
        print("it works")

s = Something()
s.out()

By defining the class before attempting to create an instance, the interpreter can successfully recognize Something and instantiate the object s.

Additionally, note that instance methods in Python require the self argument as the first parameter. This parameter represents the instance of the class that is calling the method. In the provided code, the out method was not passing self as the first argument, which would result in another type error.

By following these guidelines, you can avoid the "NameError: name is not defined" exception and ensure that your Python scripts execute successfully.

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