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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 parse_cstring(stream, offset):
 """ parse_cstring will parse a null-terminated string in a bytestream. The string will be decoded with UTF-8 decoder, of course since we are doing this byte-a-byte, it won't really work for all Unicode strings. TODO: add proper Unicode support """

    stream.seek(offset)

    string = ""

    while True:
        char = struct.unpack('c', stream.read(1))[0]

        if char == b'\x00':
            return string
        else:
            string += char.decode()