Fix not imported 'validator' (#715)

shanginn · web-flow · commit 18b14668932c · 2023-01-24T07:06:50.000-08:00
otherwise `@validator("input_variables")` do not work
diff --git a/docs/modules/prompts/examples/custom_prompt_template.md b/docs/modules/prompts/examples/custom_prompt_template.md
@@ -34,7 +34,7 @@ Next, we'll create a custom prompt template that takes in the function name as i
 
 ```python
 from langchain.prompts import BasePromptTemplate
-from pydantic import BaseModel
+from pydantic import BaseModel, validator
 
 
 class FunctionExplainerPromptTemplate(BasePromptTemplate, BaseModel):
