When is it appropriate to use a `try-except` block to handle a `KeyError` in Python?

Using a `try-except KeyError:` block is appropriate when you anticipate that a key might sometimes be missing, and you want to execute specific alternative logic or provide a fallback rather than allowing the program to crash. This approach is often favored when the absence of a key is not an unexpected error but a valid, albeit less common, scenario that requires custom handling. For example: `try: value = data_dict['required_field'] except KeyError: value = 'N/A'`.