asin_to_number.py

def asin_to_number(asin):
    """
    Convert a 10-character ASIN string to a unique number.
    This function assumes that ASIN consists of uppercase letters and digits.
    """

    def char_to_number(char):
        if char.isdigit():
            return int(char)
        else:
            return ord(char) - 55  # 'A' -> 10, 'B' -> 11, ..., 'Z' -> 35

    if len(asin) != 10:
        raise ValueError("ASIN must be 10 characters long")

    base = 36
    asin_number = 0
    for i, char in enumerate(reversed(asin)):
        asin_number += char_to_number(char) * (base ** i)

    # The final number is taken modulo 1 billion to fit the range 1-10 billion
    return asin_number % 1000000000


if __name__ == '__main__':
    x = asin_to_number('B0CGY4LZQ3')
    print(x)
    s = f'us_asin_image_part{int(x / 1000_0000) + 1}'
    print(s)