Fix: Import anthropic package when used since it's optional (#1319)

Author: CaelumF

camel/models/anthropic_model.py

@@ -14,8 +14,6 @@
 import os
 from typing import Any, Dict, List, Literal, Optional, Union
 
-from anthropic.types.beta import BetaMessageParam
-
 from camel.configs import ANTHROPIC_API_PARAMS, AnthropicConfig
 from camel.messages import OpenAIMessage
 from camel.models.base_model import BaseModelBackend
@@ -99,6 +97,7 @@ def token_counter(self) -> BaseTokenCounter:
             self._token_counter = AnthropicTokenCounter(self.model_type)
         return self._token_counter
 
+    @dependencies_required('anthropic')
     def count_tokens_from_prompt(
         self, prompt: str, role: Literal["user", "assistant"]
     ) -> int:
@@ -112,6 +111,8 @@ def count_tokens_from_prompt(
         Returns:
             int: The number of tokens in the prompt.
         """
+        from anthropic.types.beta import BetaMessageParam
+
         return self.client.beta.messages.count_tokens(
             messages=[BetaMessageParam(content=prompt, role=role)],
             model=self.model_type,

camel/utils/token_counting.py

@@ -20,7 +20,6 @@
 from math import ceil
 from typing import TYPE_CHECKING, List, Optional
 
-from anthropic.types.beta import BetaMessageParam
 from PIL import Image
 
 from camel.logger import get_logger
@@ -234,6 +233,7 @@ def __init__(self, model: str):
         self.client = Anthropic()
         self.model = model
 
+    @dependencies_required('anthropic')
     def count_tokens_from_messages(self, messages: List[OpenAIMessage]) -> int:
         r"""Count number of tokens in the provided message list using
         loaded tokenizer specific for this type of model.
@@ -245,6 +245,8 @@ def count_tokens_from_messages(self, messages: List[OpenAIMessage]) -> int:
         Returns:
             int: Number of tokens in the messages.
         """
+        from anthropic.types.beta import BetaMessageParam
+
         return self.client.beta.messages.count_tokens(
             messages=[
                 BetaMessageParam(