def is_numeric(digit: str) -> bool:
    """Kind of like `str.isdigit()` but works with
    checking for negative numbers too.
    
    Args:
        digit (str): A string to be checked for if
            it is a number.
    
    Returns:
        True if it is numeric, else false.
    """

    # Ugly but works.
    try:
        int(digit)
        return True
    except ValueError:
        return False