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diff --git a/remote/test/puppeteer/packages/puppeteer-core/src/util/Function.ts b/remote/test/puppeteer/packages/puppeteer-core/src/util/Function.ts
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index 0000000000..cdf09ba195
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+++ b/remote/test/puppeteer/packages/puppeteer-core/src/util/Function.ts
@@ -0,0 +1,98 @@
+/**
+ * Copyright 2023 Google Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+const createdFunctions = new Map<string, (...args: unknown[]) => unknown>();
+
+/**
+ * Creates a function from a string.
+ *
+ * @internal
+ */
+export const createFunction = (
+  functionValue: string
+): ((...args: unknown[]) => unknown) => {
+  let fn = createdFunctions.get(functionValue);
+  if (fn) {
+    return fn;
+  }
+  fn = new Function(`return ${functionValue}`)() as (
+    ...args: unknown[]
+  ) => unknown;
+  createdFunctions.set(functionValue, fn);
+  return fn;
+};
+
+/**
+ * @internal
+ */
+export function stringifyFunction(fn: (...args: never) => unknown): string {
+  let value = fn.toString();
+  try {
+    new Function(`(${value})`);
+  } catch {
+    // This means we might have a function shorthand (e.g. `test(){}`). Let's
+    // try prefixing.
+    let prefix = 'function ';
+    if (value.startsWith('async ')) {
+      prefix = `async ${prefix}`;
+      value = value.substring('async '.length);
+    }
+    value = `${prefix}${value}`;
+    try {
+      new Function(`(${value})`);
+    } catch {
+      // We tried hard to serialize, but there's a weird beast here.
+      throw new Error('Passed function cannot be serialized!');
+    }
+  }
+  return value;
+}
+
+/**
+ * Replaces `PLACEHOLDER`s with the given replacements.
+ *
+ * All replacements must be valid JS code.
+ *
+ * @example
+ *
+ * ```ts
+ * interpolateFunction(() => PLACEHOLDER('test'), {test: 'void 0'});
+ * // Equivalent to () => void 0
+ * ```
+ *
+ * @internal
+ */
+export const interpolateFunction = <T extends (...args: never[]) => unknown>(
+  fn: T,
+  replacements: Record<string, string>
+): T => {
+  let value = stringifyFunction(fn);
+  for (const [name, jsValue] of Object.entries(replacements)) {
+    value = value.replace(
+      new RegExp(`PLACEHOLDER\\(\\s*(?:'${name}'|"${name}")\\s*\\)`, 'g'),
+      jsValue
+    );
+  }
+  return createFunction(value) as unknown as T;
+};
+
+declare global {
+  /**
+   * Used for interpolation with {@link interpolateFunction}.
+   *
+   * @internal
+   */
+  function PLACEHOLDER<T>(name: string): T;
+}