def is_int(str_val: str) -> bool:
    """ Checks whether a string can be converted to int.

    Parameters
    ----------
    str_val : str
        A string to be checked.

    Returns
    -------
    bool
        True if can be converted to int, otherwise False
    """

    return not (len(str_val) == 0 or any([c not in "0123456789" for c in str_val]))