<｜begin▁of▁sentence｜>### Instruction:
If a function requires an optional parameter called 'threshold' that can either be an integer, a floating-point number, or None, how would you ensure that the argument provided is one of these types before proceeding with the function's calculations?
### Response:
from graspologic.preconditions import check_optional_argument_types

# Imagine we have a function that requires an optional parameter 'threshold'
# which should be either an int or a float or None.

# Here's how we might use 'check_optional_argument_types' before proceeding with our calculations
threshold = 0.5
def validate_threshold(threshold):
    required_types = (int, float)
    try:
        check_optional_argument_types(value=threshold, required_types=required_types)
        print('Threshold is valid')
    except TypeError as e:
        print(f'Invalid type: {e}')

validate_threshold(threshold)
# This should output 'Threshold is valid'
validate_threshold('a string')
# This should raise a TypeError with our custom message
<|EOT|>
