Quick function to create a admin user in WP

wp_create_admin.php

<?php

/**
 * Creates an WP admin.
 * @see         https://tommcfarlin.com/create-a-user-in-wordpress/#code
 * @see        
 * @param      string   $email_address  The email address
 * @return     boolean  
 */
function _create_admin( $email_address = '' )
{
	if( NULL == username_exists( $email_address ) ) return FALSE;

	// Generate the password and create the user
	$password = wp_generate_password( 12, FALSE );
	$user_id  = wp_create_user( $email_address, $password, $email_address );

	if ( is_wp_error( $user_id ) ) return FALSE;		
	// Set the nickname
	$user_id = wp_update_user(
		array(
			'ID'          =>    $user_id,
			'nickname'    =>    $email_address
		)
	);

	if ( is_wp_error( $user_id ) ) return FALSE;		

	// Set the role
	$user = new WP_User( $user_id );
	$user->set_role( 'administrator' );

	// Email the user
	wp_mail( $email_address, 'Welcome!', 'Your Password: ' . $password );
	return TRUE;
} // end _create_admin

_create_admin( '@gmail.com ');