Issue with inheritance in node.js: assignment error when attempting to overwrite prototype for subclass

thank you for taking the time to help me out. I'm attempting to learn node.js and have run in to the following problem when working on understanding inheritance:

var stream = require('stream');
var util = require('util');

util.inherits(Answers, stream.Readable);

function Answers(opt) {
    stream.Readable.call(this, opt);
    this.quotes = ["yes", "negatory", "possibly"];
    this._index = 0;
}

Answers.prototype._read() = function() {
    if (this._index > this.quotes.length) {
        this.push(null);
    }
    else {
        this.push(this.quotes[this._index]);
        this._index += 1;
    }
};

My error states that I have an invalid left-hand side assignment where I attempt to override the prototype of stream.Readable (line 12). I thought the call to

util.inherits(Answers, stream.Readable);

would allow me to overright the _read() function of stream.Readable. Any help would be very much appreciated. Thanks in advance!