diff --git a/core/modules/comment/lib/Drupal/comment/Entity/Comment.php b/core/modules/comment/lib/Drupal/comment/Entity/Comment.php
index 82055ec..98675be 100644
--- a/core/modules/comment/lib/Drupal/comment/Entity/Comment.php
+++ b/core/modules/comment/lib/Drupal/comment/Entity/Comment.php
@@ -13,6 +13,7 @@
 use Drupal\comment\CommentInterface;
 use Drupal\Core\Entity\EntityStorageControllerInterface;
 use Drupal\Core\Language\Language;
+use Drupal\user\UserInterface;
 
 /**
  * Defines the comment entity class.
@@ -493,4 +494,12 @@ public function setAuthorId($uid) {
     return $this;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function setAuthor(UserInterface $account) {
+    $this->set('uid', $account->id());
+    return $this;
+  }
+
 }
diff --git a/core/modules/file/lib/Drupal/file/Entity/File.php b/core/modules/file/lib/Drupal/file/Entity/File.php
index 9bbcacb..bab7e74 100644
--- a/core/modules/file/lib/Drupal/file/Entity/File.php
+++ b/core/modules/file/lib/Drupal/file/Entity/File.php
@@ -141,6 +141,14 @@ public function setAuthorId($uid) {
   /**
    * {@inheritdoc}
    */
+  public function setAuthor(UserInterface $account) {
+    $this->set('uid', $account->id());
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function isPermanent() {
     return $this->get('status')->value == FILE_STATUS_PERMANENT;
   }
diff --git a/core/modules/node/lib/Drupal/node/Entity/Node.php b/core/modules/node/lib/Drupal/node/Entity/Node.php
index 3700499..7147cd7 100644
--- a/core/modules/node/lib/Drupal/node/Entity/Node.php
+++ b/core/modules/node/lib/Drupal/node/Entity/Node.php
@@ -12,6 +12,7 @@
 use Drupal\Core\Language\Language;
 use Drupal\Core\Session\AccountInterface;
 use Drupal\node\NodeInterface;
+use Drupal\user\UserInterface;
 
 /**
  * Defines the node entity class.
@@ -296,6 +297,14 @@ public function setAuthorId($uid) {
   /**
    * {@inheritdoc}
    */
+  public function setAuthor(UserInterface $account) {
+    $this->set('uid', $account->id());
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function getRevisionCreationTime() {
     return $this->get('revision_timestamp')->value;
   }
diff --git a/core/modules/system/tests/modules/entity_test/lib/Drupal/entity_test/Entity/EntityTest.php b/core/modules/system/tests/modules/entity_test/lib/Drupal/entity_test/Entity/EntityTest.php
index 25cf73e..e0d5967 100644
--- a/core/modules/system/tests/modules/entity_test/lib/Drupal/entity_test/Entity/EntityTest.php
+++ b/core/modules/system/tests/modules/entity_test/lib/Drupal/entity_test/Entity/EntityTest.php
@@ -12,6 +12,7 @@
 use Drupal\Core\Annotation\Translation;
 use Drupal\user\EntityAuthorInterface;
 use Drupal\Core\Language\Language;
+use Drupal\user\UserInterface;
 
 /**
  * Defines the test entity class.
@@ -179,4 +180,12 @@ public function setAuthorId($uid) {
     return $this;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function setAuthor(UserInterface $account) {
+    $this->set('uid', $account->id());
+    return $this;
+  }
+
 }
diff --git a/core/modules/user/lib/Drupal/user/EntityAuthorInterface.php b/core/modules/user/lib/Drupal/user/EntityAuthorInterface.php
index cd7f4d8..63a00f3 100644
--- a/core/modules/user/lib/Drupal/user/EntityAuthorInterface.php
+++ b/core/modules/user/lib/Drupal/user/EntityAuthorInterface.php
@@ -21,6 +21,17 @@
   public function getAuthor();
 
   /**
+   * Returns the entity author's user entity.
+   *
+   * @param \Drupal\user\UserInterface $account
+   *   The author user entity.
+   *
+   * @return self
+   *   The called entity.
+   */
+  public function setAuthor(UserInterface $account);
+
+  /**
    * Returns the entity author's user ID.
    *
    * @return int