feat: support anthropic (non-streaming only) (#512)

Co-authored-by: Jason Liu <jason@jxnl.co>

docs/blog/posts/anthropic.md

@@ -0,0 +1,66 @@
+---
+draft: False
+date: 2024-03-20
+authors:
+  - jxnl
+---
+
+# Announcing Anthropic Support
+
+A special shoutout to [Shreya](https://twitter.com/shreyaw_) for her contributions to the anthropic support. As of now, all features are operational with the exception of streaming support.
+
+For those eager to experiment, simply patch the client with `ANTHROPIC_TOOLS`, which will enable you to leverage the `anthropic` client for making requests.
+
+```
+pip install instructor[anthropic]
+```
+
+```python
+from pydantic import BaseModel
+from typing import List
+import anthropic
+import instructor
+
+# Patching the Anthropics client with the instructor for enhanced capabilities
+anthropic_client = instructor.patch(
+    create=anthropic.Anthropic().messages.create,
+    mode=instructor.Mode.ANTHROPIC_TOOLS
+)
+
+class Properties(BaseModel):
+    name: str
+    value: str
+
+class User(BaseModel):
+    name: str
+    age: int
+    properties: List[Properties]
+
+user_response = anthropic_client(
+    model="claude-3-haiku-20240307",
+    max_tokens=1024,
+    max_retries=0,
+    messages=[
+        {
+            "role": "user",
+            "content": "Create a user for a model with a name, age, and properties.",
+        }
+    ],
+    response_model=User,
+)  # type: ignore
+
+print(user_response.model_dump_json(indent=2))
+"""
+{
+    "name": "John",
+    "age": 25,
+    "properties": [
+        {
+            "key": "favorite_color",
+            "value": "blue"
+        }
+    ]
+}
+```
+
+We're encountering challenges with deeply nested types and eagerly invite the community to test, provide feedback, and suggest necessary improvements as we enhance the anthropic client's support.