* @param sources The dependency management sections to import, may be <code>null</code>.
     * @param request The model building request that holds further settings, must not be {@code null}.
     * @param problems The container used to collect problems that were encountered, must not be {@code null}.
     */
    void importManagement(

// unless that metadata is needed in order to allow a subsequent data retrieval
// to  be  correctly  handled.   For example, changes to st_atime or st_mtime
// (respectively, time of last access and time of last modification; see inode(7))
// do not require flushing because they are not necessary for a subsequent data
// read to be handled correctly. On the other hand, a change to the file size

allows individual programs to opt back in to the old behavior.
A GODEBUG setting may not be added if doing so is infeasible,
but that should be extremely rare.

GODEBUG settings added for compatibility will be maintained
for a minimum of two years (four Go releases).
Some, such as `http2client` and `http2server`,
will be maintained much longer, even indefinitely.

When possible, each GODEBUG setting has an associated

{* ../../docs_src/extra_models/tutorial002_py310.py hl[7,13:14,17:18,21:22] *}

## `Union` or `anyOf` { #union-or-anyof }

You can declare a response to be the `Union` of two or more types, that means, that the response would be any of them.

It will be defined in OpenAPI with `anyOf`.

	if err := DB.Model(&user2).Association("Account").Append(&account); err != nil {
		t.Fatalf("Error happened when append account, got %v", err)
	}

	if account.ID == 0 {
		t.Fatalf("Account's ID should be created")
	}

	user.Account = account
	CheckUser(t, user2, user)

	AssertAssociationCount(t, user, "Account", 1, "AfterAppend")

	// Replace
	account2 := Account{Number: "account-has-one-replace"}

	writer := WriteOnClose(io.Discard)
	if writer.HasWritten() {
		t.Error("WriteOnCloser must not be marked as HasWritten")
	}
	writer.Write(nil)
	if !writer.HasWritten() {
		t.Error("WriteOnCloser must be marked as HasWritten")
	}

	writer = WriteOnClose(io.Discard)
	writer.Close()
	if !writer.HasWritten() {
		t.Error("WriteOnCloser must be marked as HasWritten")
	}
}

// Test for AppendFile.

  /**
   * The current state of the service. This should be written with the lock held but can be read
   * without it because it is an immutable object in a volatile field. This is desirable so that
   * methods like {@link #state}, {@link #failureCause} and notably {@link #toString} can be run
   * without grabbing the lock.
   *
   * <p>To update this field correctly the lock must be held to guarantee that the state is
   * consistent.
   */

	if DB.Model(&users).Association("Toys").Find(&toys); len(toys) != 6 {
		t.Errorf("toys count should be %v, but got %v", 6, len(toys))
	}

	// Find Tools (polymorphic with custom type and id)
	var tools []Tools
	DB.Model(&users).Association("Tools").Find(&tools)

	if len(tools) != 2 {
		t.Errorf("tools count should be %v, but got %v", 2, len(tools))
	}

	// Append
	DB.Model(&users).Association("Toys").Append(

     *
     * <p>If the graph is directed, the resultant edge will be directed; otherwise, it will be
     * undirected.
     *
     * <p>If this graph is directed, {@code endpoints} must be ordered.
     *
     * <p>Values do not have to be unique. However, values must be non-null.
     *
     * <p>If either or both endpoints are not already present in this graph, this method will

	}

	tx2.Commit()
	// Attempt to convert the connection pool of tx to the *gorm.PreparedStmtDB type.
	// If the conversion is successful, ok will be true and conn will be the converted object;
	// otherwise, ok will be false and conn will be nil.
	conn, ok := tx.ConnPool.(*gorm.PreparedStmtDB)
	// Get the number of statement keys stored in the PreparedStmtDB.
	lens := len(conn.Stmts.Keys())