import string


def get_tilt_series_label(tiltnumber):
    """Generates a tilt series label using the alphabet as a base 26 number
       system
       For example 0 would = a 25 = z 26 = ba 27 = bb
       (there is no aa cause a=0)
       :returns: tiltseries label by converting tiltnumber to base 26
    """
    base = 26
    convertedval = ''
    num = int(tiltnumber)
    while num >= base:
        nextchar = num % base
        convertedval = string.ascii_lowercase[nextchar] + convertedval
        num = int(num / base)

    convertedval = string.ascii_lowercase[num] + convertedval
    return convertedval