code: def test_composed_pydantic_grammar():
      """
      from pydantic import BaseModel
  
      class A(BaseModel):
          a: int
  
      class B(BaseModel):
          a: A
          b: int
      """
  
      # This schema corresponds to the grammar in the comment above.
      # We don't use the pydantic models directly to avoid the dependency.
      schema = {
          "$defs": {
              "A": {
                  "properties": {
                      "a": {"title": "A", "type": "integer"}
                  },
                  "required": ["a"],
                  "title": "A",
                  "type": "object",
              }
          },
          "properties": {
              "a": {"$ref": "#/$defs/A"},
              "b": {"title": "B", "type": "integer"},
          },
          "required": ["a", "b"],
          "title": "B",
          "type": "object",
      }
  
      grammar = llama_cpp.LlamaGrammar.from_json_schema(
          json.dumps(schema)
      )
  
      assert grammar.grammar is not None
  
imports: import llama_cpp
  import json
label_desc: Use image node_id 2 for calling a global function with example usage: test_composed_pydantic_grammar() without return types