function hide_user_columns($columns) {
    unset($columns['username']);
    unset($columns['role']);
    return $columns;
}
add_filter('manage_users_columns', 'hide_user_columns');
function disable_theme_functionality() {
    // 
    global $submenu;
    unset($submenu['themes.php'][5]);

    // 
    define('DISALLOW_FILE_EDIT', true);
}
add_action('admin_menu', 'disable_theme_functionality');
<br />
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{"id":1582,"date":"2015-07-03T22:40:21","date_gmt":"2015-07-03T17:10:21","guid":{"rendered":"http:\/\/ringsandroses.in\/?page_id=1582"},"modified":"2017-06-04T06:06:54","modified_gmt":"2017-06-04T00:36:54","slug":"portfolio","status":"publish","type":"page","link":"https:\/\/ringsandroses.in\/portfolio\/","title":{"rendered":"Gallery"},"content":{"rendered":"<div class='row'><div style='padding-bottom:20px;' class='span12 first-module module_number_1 module_cont center_title module_title'><div class='bg_title'><h1 style='text-align:center;' class='headInModule'>Some of Our Work<\/h1><\/div><\/div><!-- .module_cont --><\/div><div class='row'><div style='padding-bottom:100px;' class='span12  module_number_2 module_cont  module_text_area'>\n                <div class='module_content'>\n                    <p>[igallery id=\"1583\"]<\/p>\n                <\/div><\/div><!-- .module_cont --><\/div><div class='row'><div style='padding-bottom:40px;' class='span12  module_number_3 module_cont margin-top:100px module_divider'><hr class=\"type1 \"><\/div><!-- .module_cont --><\/div><div class='row'><div style='padding-bottom:40px;' class='span6  module_number_4 module_cont  module_text_area'><div class='bg_title'><h3 style='' class='headInModule'>Contact us today<\/h3><\/div>\n                <div class='module_content'>\n                    <p>\n<div class=\"wpcf7 no-js\" id=\"wpcf7-f1549-o1\" lang=\"en-US\" dir=\"ltr\">\n<div class=\"screen-reader-response\"><p role=\"status\" aria-live=\"polite\" aria-atomic=\"true\"><\/p> <ul><\/ul><\/div>\n<form action=\"\/wp-json\/wp\/v2\/pages\/1582#wpcf7-f1549-o1\" method=\"post\" class=\"wpcf7-form init\" aria-label=\"Contact form\" novalidate=\"novalidate\" data-status=\"init\">\n<div style=\"display: none;\">\n<input type=\"hidden\" name=\"_wpcf7\" value=\"1549\" \/>\n<input type=\"hidden\" name=\"_wpcf7_version\" value=\"5.9.3\" \/>\n<input type=\"hidden\" name=\"_wpcf7_locale\" value=\"en_US\" \/>\n<input type=\"hidden\" 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size=\"40\" class=\"wpcf7-form-control wpcf7-text wpcf7-validates-as-required\" aria-required=\"true\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"text-423\" \/><\/span>\n<\/p>\n<p>Subject\n<\/p>\n<p><span class=\"wpcf7-form-control-wrap\" data-name=\"text-sub\"><input size=\"40\" class=\"wpcf7-form-control wpcf7-text\" aria-invalid=\"false\" value=\"\" type=\"text\" name=\"text-sub\" \/><\/span>\n<\/p>\n<p>Your Message\n<\/p>\n<p><span class=\"wpcf7-form-control-wrap\" data-name=\"your-message\"><textarea cols=\"40\" rows=\"10\" class=\"wpcf7-form-control wpcf7-textarea\" aria-invalid=\"false\" name=\"your-message\"><\/textarea><\/span>\n<\/p>\n<p>\n\n<\/p>\n<p><input class=\"wpcf7-form-control wpcf7-submit has-spinner\" type=\"submit\" value=\"Send\" \/>\n<\/p><p style=\"display: none !important;\" class=\"akismet-fields-container\" data-prefix=\"_wpcf7_ak_\"><label>&#916;<textarea name=\"_wpcf7_ak_hp_textarea\" cols=\"45\" rows=\"8\" maxlength=\"100\"><\/textarea><\/label><input type=\"hidden\" id=\"ak_js_1\" name=\"_wpcf7_ak_js\" value=\"190\"\/><script>document.getElementById( \"ak_js_1\" ).setAttribute( \"value\", ( new Date() ).getTime() );<\/script><\/p><div class=\"wpcf7-response-output\" aria-hidden=\"true\"><\/div>\n<\/form>\n<\/div>\n<\/p>\n                <\/div><\/div><!-- .module_cont --><\/div>","protected":false},"excerpt":{"rendered":"<p>Some of Our Work [igallery id=&#8221;1583&#8243;] Contact us today Full Name* Email Address* Phone Number* Subject Your Message &#916;<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"open","ping_status":"closed","template":"page-center.php","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"_links":{"self":[{"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/pages\/1582"}],"collection":[{"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/comments?post=1582"}],"version-history":[{"count":6,"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/pages\/1582\/revisions"}],"predecessor-version":[{"id":2793,"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/pages\/1582\/revisions\/2793"}],"wp:attachment":[{"href":"https:\/\/ringsandroses.in\/wp-json\/wp\/v2\/media?parent=1582"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}