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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _reorder(string, salt):
 """Reorders `string` according to `salt`."""

    len_salt = len(salt)

    if len_salt != 0:
        string = list(string)
        index, integer_sum = 0, 0
        for i in range(len(string) - 1, 0, -1):
            integer = ord(salt[index])
            integer_sum += integer
            j = (integer + index + integer_sum) % i
            string[i], string[j] = string[j], string[i]
            index = (index + 1) % len_salt
        string = ''.join(string)

    return string