"""Calculate the size and number of elements for a given struct format.

This function computes two values based on the provided struct format string:
1. The size in bytes required to store the data described by the format.
2. The number of elements that would be unpacked from a byte sequence of that size.

Args:
    format (str): A format string as defined by the `struct` module, specifying the data layout.

Returns:
    tuple: A tuple containing two integers:
        - The first integer is the size in bytes of the data described by the format.
        - The second integer is the number of elements that would be unpacked from a byte sequence of that size.
"""
You should write code starting with:
import struct

def _formatinfo(format: str) -> tuple[int, int]:
    # TODO: Implement this function
    pass

