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: OBJECTIVE : The objective of this study was to determine the risk of lifetime and current methamphetamine - induced psychosis in patients with methamphetamine dependence .
### Output Text:
OBJECTIVE : The objective of this study was to determine the risk of lifetime and current <span class="chemical">methamphetamine</span> - induced psychosis in patients with <span class="chemical">methamphetamine</span> dependence . 