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// takes an array of bytes and returns the first varint that// it can find and the number of bytes it read, varints are// encoded using LEN128export function readVarInt(bytes) {    let mask128 = 128 // 10000000    let varIntSize = 0    for (let i = 0; i < bytes.length; i++) {	if ((bytes[i] & mask128) > 0) {	    varIntSize++	} else {	    varIntSize++	    break	}    }
    let varInt = 0    let mask127 = 127 // 01111111
    for (let i = 0; i < varIntSize; i++) {	varInt += (bytes[i] & mask127) << (i * 7)    }
    return { varInt, varIntSize }}
// takes an integer, encodes it using LEN128 and returns// the byte array result as a Uint8Arrayexport function makeVarInt(num) {    let numberOfBits = 0
    for (let i = 0; i < 64; i++) {	if ((num >>> i) > 0) {	    numberOfBits++	} else {	    numberOfBits++	    break	}    }
    let varIntBytes = new Uint8Array(Math.floor(numberOfBits / 7) + 1)    let mask128 = 128 // 100000000    for (let i = 0; i < varIntBytes.length; i++) {	varIntBytes[i] = (num >>> (i * 7)) | mask128    }
    let mask127 = 127 // 01111111    varIntBytes[varIntBytes.length-1] = varIntBytes[varIntBytes.length-1] & mask127
    return varIntBytes}