In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The liver biochemistries eventually normalized within 3 weeks of stopping the fluvastatin .
### Output Text:
The liver biochemistries eventually normalized within 3 weeks of stopping the <span class="chemical">fluvastatin</span> . 