/* Landline Icon for Contact Us Page */
function sws_landline_icon()
{$output = '<img width = "40" height="40" shortcut icon" src="data:image/png;base64,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" class="sws-icon" alt="contact" title="contact">';
return $output;
} add_shortcode('sws-landline','sws_landline_icon');
Example of shortcode 