UTF-8 Validation Python Solution with Tests

lcpy gen -n 393   # by problem number
lcpy gen -s utf_8_validation   # by problem name

     Number of Bytes   |        UTF-8 Octet Sequence
                       |              (binary)
   --------------------+-----------------------------------------
            1          |   0xxxxxxx
            2          |   110xxxxx 10xxxxxx
            3          |   1110xxxx 10xxxxxx 10xxxxxx
            4          |   11110xxx 10xxxxxx 10xxxxxx 10xxxxxx

Input: data = [197,130,1]
Output: true
Explanation: data represents the octet sequence: 11000101 10000010 00000001.
It is a valid utf-8 encoding for a 2-bytes character followed by a 1-byte character.

Input: data = [235,140,4]
Output: false
Explanation: data represented the octet sequence: 11101011 10001100 00000100.
The first 3 bits are all one's and the 4th bit is 0 means it is a 3-bytes character.
The next byte is a continuation byte which starts with 10 and that's correct.
But the second continuation byte does not start with 10, so it is invalid.

class Solution:
    # Time: O(n)
    # Space: O(1)
    def valid_utf8(self, data: list[int]) -> bool:
        remaining = 0
        for byte in data:
            if remaining == 0:
                if byte >> 7 == 0b0:
                    remaining = 0
                elif byte >> 5 == 0b110:
                    remaining = 1
                elif byte >> 4 == 0b1110:
                    remaining = 2
                elif byte >> 3 == 0b11110:
                    remaining = 3
                else:
                    return False
            else:
                if byte >> 6 != 0b10:
                    return False
                remaining -= 1
        return remaining == 0