For theme developer demo data is a must have content to check the them design. First you need to download Theme Unit Test xml file from Here. Then you need to install WordPress Importer Plugin from Here
Use the XML File to Import the Demo Site’s Content
- Log into your site as an administrator.
- Go to Tools → Import
- Choose “WordPress” from the list.
- Upload the demo content .xml using the form provided on that page.
- You will be asked to map the authors in this export file to users on the blog. For each author, you may choose to map to an existing user on the blog or to create a new user.
- You will then have the choice to import attachments, so click on the “Download and import file attachments” box.
- Please be patient while WordPress imports all the content.
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