@staticmethod
def int_to_binary(card_int):
    """
        For debugging purposes. Displays the binary number as a 
        human readable string in groups of four digits. 
        """
    bstr = bin(card_int)[2:][::-1]
    output = list(''.join(['0000' + '\t'] * 7) + '0000')
    for i in range(len(bstr)):
        output[i + int(i / 4)] = bstr[i]
    output.reverse()
    return ''.join(output)
