def __init__(self) -> None:
        """Initialize timer callback.

        The callback initializes:
        - ``start``: Timestamp for tracking execution segments
        - ``num_images``: Counter for total test images
        """
        self.start: float
        self.num_images: int = 0
Initialize timer callback.

        The callback initializes:
        - ``start``: Timestamp for tracking execution segments
        - ``num_images``: Counter for total test images
        
src/anomalib/callbacks/timer.py