text: import { keys } from "./keys.js";
  import { property } from "./property.js";
  import { defineProperty } from "./defineProperty.js";
  import { symbols } from "./symbols.js";
  
  export const extend = (target, ...sources) => {
    sources.forEach((source) => {
      keys(source).forEach((key) => {
        if (key === "prototype") {
          target[key] = source[key];
        } else {
          defineProperty(target, key, property(source, key));
        }
      });
      symbols(source).forEach((symbol) => {
        defineProperty(target, symbol, property(source, symbol));
      });
    });
    return target;
  };
  