def is_int(potential_int: str) -> bool:
    """
    Check if potential_int is a valid integer.

    Parameters
    ----------
    potential_int : str

    Returns
    -------
    is_int : bool

    Examples
    --------
    >>> is_int('123')
    True
    >>> is_int('1234567890123456789')
    True
    >>> is_int('0')
    True
    >>> is_int('-123')
    True
    >>> is_int('123.45')
    False
    >>> is_int('a')
    False
    >>> is_int('0x8')
    False
    """
    try:
        int(potential_int)
        return True
    except ValueError:
        return False