import string


def ind2chr(index):
    """c = ind2chr(i)

    Convert the index i to a character c, so that 0 -> 'A', 1 -> 'B',
    etc. Invalid indexes convert to the character '*'.
    """
    index = int(index)
    if index < 0 or index >= len(string.ascii_uppercase):
        return "*"
    return string.ascii_uppercase[index]