unable to add menu in wordpress
<pre><code>    $page_title = "PushBIZ.IN";
    $menu_title = "PushBIZ.IN";
    $capability = 'activate_plugins';
    $menu_slug  = "pushbiz";
    $function   = "PushBIZIN_first";

    add_menu_page( __('Getting Started'), $menu_title, $capability, $menu_slug, array($this, $function), plugins_url( WPPUSH_APPNAME.'/assets/images/app20x20.png' ) ); 
    add_submenu_page( $menu_slug, __('BIZ Message'), __('BIZ Message'), $capability, 'BIZMessage', array($this, 'BIZ_Message') );   
    add_submenu_page( $menu_slug, __('Business Analyst'), __('Business Analyst'), $capability, 'businessanalyst', array($this, 'business_analyst') );
    add_submenu_page( $menu_slug, __('BIZ Interests'), __('BIZ Interests'), $capability, 'BIZinterests', array($this, 'BIZ_interests') );
</code></pre>

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