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: In contrast reports indicate that hippocampal dependent neurogenesis and cognition are enhanced by the SSRI antidepressant Fluoxetine .
### Output Text:
In contrast reports indicate that hippocampal dependent neurogenesis and cognition are enhanced by the <span class="chemical">SSRI</span> antidepressant <span class="chemical">Fluoxetine</span> . 