You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <images imcontinue="1|District8_banner.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page">
        <images>
          <im ns="6" title="File:District10 banner.png" />
          <im ns="6" title="File:District11 banner.png" />
          <im ns="6" title="File:District12 banner.png" />
          <im ns="6" title="File:District1 banner.png" />
          <im ns="6" title="File:District2 banner.png" />
          <im ns="6" title="File:District3 banner.png" />
          <im ns="6" title="File:District4 banner.png" />
          <im ns="6" title="File:District5 banner.png" />
          <im ns="6" title="File:District6 banner.png" />
          <im ns="6" title="File:District7 banner.png" />
        </images>
      </page>
    </pages>
  </query>
</api>