Add AI21 LLMs (#99)

Integrate AI21 /complete API into langchain, to allow access to Jurassic
models.

langchain/llms/ai21.py

@@ -0,0 +1,132 @@
+"""Wrapper around AI21 APIs."""
+import os
+from typing import Any, Dict, List, Mapping, Optional
+
+import requests
+from pydantic import BaseModel, Extra, root_validator
+
+from langchain.llms.base import LLM
+
+
+class AI21PenaltyData(BaseModel):
+    scale: int = 0
+    applyToWhitespaces: bool = True
+    applyToPunctuations: bool = True
+    applyToNumbers: bool = True
+    applyToStopwords: bool = True
+    applyToEmojis: bool = True
+
+
+class AI21(BaseModel, LLM):
+    """Wrapper around AI21 large language models.
+
+    To use, you should have the environment variable ``AI21_API_KEY`` set with your API key.
+
+    Example:
+        .. code-block:: python
+
+            from langchain import AI21
+            ai21 = AI21(model="j1-jumbo")
+    """
+
+    model: str = "j1-jumbo"
+    """Model name to use."""
+
+    temperature: float = 0.7
+    """What sampling temperature to use."""
+
+    maxTokens: int = 256
+    """The maximum number of tokens to generate in the completion."""
+
+    minTokens: int = 0
+    """The minimum number of tokens to generate in the completion."""
+
+    topP: float = 1.0
+    """Total probability mass of tokens to consider at each step."""
+
+    presencePenalty: AI21PenaltyData = AI21PenaltyData()
+    """Penalizes repeated tokens."""
+
+    countPenalty: AI21PenaltyData = AI21PenaltyData()
+    """Penalizes repeated tokens according to count."""
+
+    frequencyPenalty: AI21PenaltyData = AI21PenaltyData()
+    """Penalizes repeated tokens according to frequency."""
+
+    numResults: int = 1
+    """How many completions to generate for each prompt."""
+
+    logitBias: Dict[str, float] = None
+    """Adjust the probability of specific tokens being generated."""
+
+    ai21_api_key: Optional[str] = os.environ.get("AI21_API_KEY")
+
+    class Config:
+        """Configuration for this pydantic object."""
+
+        extra = Extra.forbid
+
+    @root_validator()
+    def validate_environment(cls, values: Dict) -> Dict:
+        """Validate that api key exists in environment."""
+        ai21_api_key = values.get("ai21_api_key")
+
+        if ai21_api_key is None or ai21_api_key == "":
+            raise ValueError(
+                "Did not find AI21 API key, please add an environment variable"
+                " `AI21_API_KEY` which contains it, or pass `ai21_api_key`"
+                " as a named parameter."
+            )
+        return values
+
+    @property
+    def _default_params(self) -> Mapping[str, Any]:
+        """Get the default parameters for calling AI21 API."""
+        return {
+            "temperature": self.temperature,
+            "maxTokens": self.maxTokens,
+            "minTokens": self.minTokens,
+            "topP": self.topP,
+            "presencePenalty": self.presencePenalty.dict(),
+            "countPenalty": self.countPenalty.dict(),
+            "frequencyPenalty": self.frequencyPenalty.dict(),
+            "numResults": self.numResults,
+            "logitBias": self.logitBias,
+        }
+
+    @property
+    def _identifying_params(self) -> Mapping[str, Any]:
+        """Get the identifying parameters."""
+        return {**{"model": self.model}, **self._default_params}
+
+    def __call__(self, prompt: str, stop: Optional[List[str]] = None) -> str:
+        """Call out to AI21's complete endpoint.
+
+        Args:
+            prompt: The prompt to pass into the model.
+            stop: Optional list of stop words to use when generating.
+
+        Returns:
+            The string generated by the model.
+
+        Example:
+            .. code-block:: python
+
+                response = ai21("Tell me a joke.")
+        """
+        if stop is None:
+            stop = []
+        response = requests.post(
+            url=f"https://api.ai21.com/studio/v1/{self.model}/complete",
+            headers={"Authorization": f"Bearer {self.ai21_api_key}"},
+            json={
+                "prompt": prompt,
+                "stopSequences": stop,
+                **self._default_params,
+            }
+        )
+        if response.status_code != 200:
+            optional_detail = response.json().get('error')
+            raise ValueError(f'AI21 /complete call failed with status code {response.status_code}. Details: {optional_detail}')
+        response = response.json()
+        return response["completions"][0]["data"]["text"]

tests/integration_tests/llms/test_ai21.py

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+"""Test AI21 API wrapper."""
+
+from langchain.llms.ai21 import AI21
+
+
+def test_ai21_call() -> None:
+    """Test valid call to ai21."""
+    llm = AI21(maxTokens=10)
+    output = llm("Say foo:")
+    assert isinstance(output, str)