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: Alterations of norepinephrine transporter ( NET ) function by chronic inhibition of NET in relation to sensitization to seizures induce by cocaine and local anesthetics were studied in mice .
### Output Text:
Alterations of <span class="chemical">norepinephrine</span> transporter ( NET ) function by chronic inhibition of NET in relation to sensitization to seizures induce by <span class="chemical">cocaine</span> and local anesthetics were studied in mice . 