# Validate template

By default, `PromptTemplate` will validate the `template` string by checking whether the `input_variables` match the variables defined in `template`. You can disable this behavior by setting `validate_template` to `False`

```python
template = "I am learning langchain because {reason}."

prompt_template = PromptTemplate(template=template,
                                 input_variables=["reason", "foo"]) # ValueError due to extra variables
prompt_template = PromptTemplate(template=template,
                                 input_variables=["reason", "foo"],
                                 validate_template=False) # No error
```