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: Although generally well - tolerated , asymptomatic abnormalities of liver function have been recorded and , less commonly , severe hepatitis induced by diclofenac .
### Output Text:
Although generally well - tolerated , asymptomatic abnormalities of liver function have been recorded and , less commonly , severe hepatitis induced by <span class="chemical">diclofenac</span> . 