How to Check for Variable Existence in Python Without Using Exceptions?

How to Determine Variable Existence Without Exceptions

In Python, it's common to verify variable existence using try/except blocks:

try:
    myVar
except NameError:
    # Do something.

However, there are alternative approaches to accomplish this without exceptions.

Checking Local Variables

To check if a local variable exists, use if with locals():

if 'myVar' in locals():
    # myVar exists.

Checking Global Variables

Similarly, for global variables, use if with globals():

if 'myVar' in globals():
    # myVar exists.

Checking Object Attributes

To determine if an object has a specific attribute, use hasattr():

if hasattr(obj, 'attr_name'):
    # obj.attr_name exists.

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