def baseconv(num, alphabet, minimum_characters=0):
    """
    convert base 10 number to custom base w/ alphabet
    :param num: base 10 input
    :param alphabet: alphabet to use for conversion
    :return:
    """
    arr = []
    base = len(alphabet)
    if not num:
        converted_value = alphabet[0]
    else:
        while num:
            rem = num % base
            num //= base
            arr.append(alphabet[rem])
        arr.reverse()
        converted_value = str(''.join(arr))
    while len(converted_value) < minimum_characters:
        converted_value = alphabet[0] + converted_value
    return converted_value
