[Bug fix] Anthropic, Llama2 and VertexAI LLMs dependencies (#820)

embedchain/llm/anthropic.py

@@ -1,4 +1,5 @@
 import logging
+import os
 from typing import Optional
 
 from embedchain.config import BaseLlmConfig
@@ -9,6 +10,8 @@ from embedchain.llm.base import BaseLlm
 @register_deserializable
 class AnthropicLlm(BaseLlm):
     def __init__(self, config: Optional[BaseLlmConfig] = None):
+        if "ANTHROPIC_API_KEY" not in os.environ:
+            raise ValueError("Please set the ANTHROPIC_API_KEY environment variable.")
         super().__init__(config=config)
 
     def get_llm_model_answer(self, prompt):
@@ -18,7 +21,9 @@ class AnthropicLlm(BaseLlm):
     def _get_answer(prompt: str, config: BaseLlmConfig) -> str:
         from langchain.chat_models import ChatAnthropic
 
-        chat = ChatAnthropic(temperature=config.temperature, model=config.model)
+        chat = ChatAnthropic(
+            anthropic_api_key=os.environ["ANTHROPIC_API_KEY"], temperature=config.temperature, model=config.model
+        )
 
         if config.max_tokens and config.max_tokens != 1000:
             logging.warning("Config option `max_tokens` is not supported by this model.")