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function is not described

wpmu_create_user() WP 3.0.0

Create a user.

This function runs when a user self-registers as well as when a Super Admin creates a new user. Hook to 'wpmu_new_user' for events that should affect all new users, but only on Multisite (otherwise use {@see'user_register'}).

Hooks in function
Return

Int/false. Returns false on failure, or int $user_id on success

Usage

wpmu_create_user( $user_name, $password, $email );
$user_name(string) (required)
The new user's login name.
$password(string) (required)
The new user's password.
$email(string) (required)
The new user's email address.

Code of wpmu create user: wp-includes/ms-functions.php WP 5.2.2

<?php
function wpmu_create_user( $user_name, $password, $email ) {
	$user_name = preg_replace( '/\s+/', '', sanitize_user( $user_name, true ) );

	$user_id = wp_create_user( $user_name, $password, $email );
	if ( is_wp_error( $user_id ) ) {
		return false;
	}

	// Newly created users have no roles or caps until they are added to a blog.
	delete_user_option( $user_id, 'capabilities' );
	delete_user_option( $user_id, 'user_level' );

	/**
	 * Fires immediately after a new user is created.
	 *
	 * @since MU (3.0.0)
	 *
	 * @param int $user_id User ID.
	 */
	do_action( 'wpmu_new_user', $user_id );

	return $user_id;
}