viruPVS/langchain-docs huggingface dataset:
Chain.input_keys except for inputs that will be set by the chain’s
memory.
return_only_outputs – Whether to return only outputs in the
response. If True, only new keys generated by this chain will be
returned. If False, both input keys and new keys generated by this
chain will be returned. Defaults to False.
callbacks – Callbacks to use for this chain run. These will be called in
addition to callbacks passed to the chain during construction, but only
these runtime callbacks will propagate to calls to other objects.
tags – List of string tags to pass to all callbacks. These will be passed in
addition to tags passed to the chain during construction, but only
these runtime tags will propagate to calls to other objects.
metadata – Optional metadata associated with the chain. Defaults to None
include_run_info – Whether to include run info in the response. Defaults
to False.
Returns
A dict of named outputs. Should contain all outputs specified inChain.output_keys.
async ainvoke(input: Dict[str, Any], config: Optional[RunnableConfig] = None, **kwargs: Any) → Dict[str, Any]¶
Default implementation of ainvoke, calls invoke from a thread.
The default implementation allows usage of async code even if
the runnable did not implement a native async version of invoke.
Subclasses should override this method if they can run asynchronously.
apply(input_list: List[Dict[str, Any]], callbacks: Optional[Union[List[BaseCallbackHandler], BaseCallbackManager]] = None) → List[Dict[str, str]]¶
Call the chain on all inputs in the list.
async arun(*args: Any, callbacks: Optional[Union[List[BaseCallbackHandler], BaseCallbackManager]] = None, tags: Optional[List[str]] = None, metadata: Optional[Dict[str, Any]] = None, **kwargs: Any) → Any¶
Default values are respected, but no other validation is performed.
Behaves as if Config.extra = ‘allow’ was set since it adds all passed values
copy(*, include: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, exclude: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, update: Optional[DictStrAny] = None, deep: bool = False) → Model¶
Duplicate a model, optionally choose which fields to include, exclude and change.
Parameters
include – fields to include in new model
exclude – fields to exclude from new model, as with values this takes precedence over include
update – values to change/add in the new model. Note: the data is not validated before creating
the new model: you should trust this data
deep – set to True to make a deep copy of the model
Returns
new model instance
dict(**kwargs: Any) → Dict¶
Dictionary representation of chain.
Expects Chain._chain_type property to be implemented and for memory to benull.
Parameters
**kwargs – Keyword arguments passed to default pydantic.BaseModel.dict
method.
Returns
A dictionary representation of the chain.
Example
chain.dict(exclude_unset=True)
# -> {"_type": "foo", "verbose": False, ...}
classmethod from_orm(obj: Any) → Model¶
classmethod from_retrievers(llm: BaseLanguageModel, retriever_infos: List[Dict[str, Any]], default_retriever: Optional[BaseRetriever] = None, default_prompt: Optional[PromptTemplate] = None, default_chain: Optional[Chain] = None, **kwargs: Any) → MultiRetrievalQAChain[source]¶
get_input_schema(config: Optional[RunnableConfig] = None) → Type[BaseModel]¶
langchain.chains.conversational_retrieval.base.ConversationalRetrievalChain¶
class langchain.chains.conversational_retrieval.base.ConversationalRetrievalChain[source]¶
Bases: BaseConversationalRetrievalChain
Chain for having a conversation based on retrieved documents.
This chain takes in chat history (a list of messages) and new questions,
and then returns an answer to that question.
The algorithm for this chain consists of three parts:
1. Use the chat history and the new question to create a “standalone question”.
This is done so that this question can be passed into the retrieval step to fetch
relevant documents. If only the new question was passed in, then relevant context
may be lacking. If the whole conversation was passed into retrieval, there may
be unnecessary information there that would distract from retrieval.
2. This new question is passed to the retriever and relevant documents are
returned.
3. The retrieved documents are passed to an LLM along with either the new question
(default behavior) or the original question and chat history to generate a final
response.
Example
from langchain.chains import (
    StuffDocumentsChain, LLMChain, ConversationalRetrievalChain
)
from langchain_core.prompts import PromptTemplate
from langchain.llms import OpenAI
combine_docs_chain = StuffDocumentsChain(...)
vectorstore = ...
retriever = vectorstore.as_retriever()
# This controls how the standalone question is generated.
# Should take `chat_history` and `question` as input variables.
template = (
    "Combine the chat history and follow up question into "
    "a standalone question. Chat History: {chat_history}"
    "Follow up question: {question}"
)
prompt = PromptTemplate.from_template(template)
llm = OpenAI()
)
prompt = PromptTemplate.from_template(template)
llm = OpenAI()
question_generator_chain = LLMChain(llm=llm, prompt=prompt)
chain = ConversationalRetrievalChain(
    combine_docs_chain=combine_docs_chain,
    retriever=retriever,
    question_generator=question_generator_chain,
)
Create a new model by parsing and validating input data from keyword arguments.
Raises ValidationError if the input data cannot be parsed to form a valid model.
param callback_manager: Optional[BaseCallbackManager] = None¶
Deprecated, use callbacks instead.
param callbacks: Callbacks = None¶
Optional list of callback handlers (or callback manager). Defaults to None.
Callback handlers are called throughout the lifecycle of a call to a chain,
starting with on_chain_start, ending with on_chain_end or on_chain_error.
Each custom chain can optionally call additional callback methods, see Callback docs
for full details.
param combine_docs_chain: BaseCombineDocumentsChain [Required]¶
The chain used to combine any retrieved documents.
param get_chat_history: Optional[Callable[[List[CHAT_TURN_TYPE]], str]] = None¶
An optional function to get a string of the chat history.
If None is provided, will use a default.
param max_tokens_limit: Optional[int] = None¶
If set, enforces that the documents returned are less than this limit.
This is only enforced if combine_docs_chain is of type StuffDocumentsChain.
param memory: Optional[BaseMemory] = None¶
Optional memory object. Defaults to None.
Memory is a class that gets called at the start
and at the end of every chain. At the start, memory loads variables and passes
them along in the chain. At the end, it saves any returned variables.
There are many different types of memory - please see memory docs
There are many different types of memory - please see memory docs
for the full catalog.
param metadata: Optional[Dict[str, Any]] = None¶
Optional metadata associated with the chain. Defaults to None.
This metadata will be associated with each call to this chain,
and passed as arguments to the handlers defined in callbacks.
You can use these to eg identify a specific instance of a chain with its use case.
param output_key: str = 'answer'¶
The output key to return the final answer of this chain in.
param question_generator: LLMChain [Required]¶
The chain used to generate a new question for the sake of retrieval.
This chain will take in the current question (with variable question)
and any chat history (with variable chat_history) and will produce
a new standalone question to be used later on.
param rephrase_question: bool = True¶
Whether or not to pass the new generated question to the combine_docs_chain.
If True, will pass the new generated question along.
If False, will only use the new generated question for retrieval and pass the
original question along to the combine_docs_chain.
param response_if_no_docs_found: Optional[str] = None¶
If specified, the chain will return a fixed response if no docs
are found for the question.
param retriever: BaseRetriever [Required]¶
Retriever to use to fetch documents.
param return_generated_question: bool = False¶
Return the generated question as part of the final result.
param return_source_documents: bool = False¶
Return the retrieved source documents as part of the final result.
param tags: Optional[List[str]] = None¶
Optional list of tags associated with the chain. Defaults to None.
These tags will be associated with each call to this chain,
and passed as arguments to the handlers defined in callbacks.
to False.
Returns
A dict of named outputs. Should contain all outputs specified inChain.output_keys.
async abatch(inputs: List[Input], config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None, *, return_exceptions: bool = False, **kwargs: Optional[Any]) → List[Output]¶
Default implementation runs ainvoke in parallel using asyncio.gather.
The default implementation of batch works well for IO bound runnables.
Subclasses should override this method if they can batch more efficiently;
e.g., if the underlying runnable uses an API which supports a batch mode.
async acall(inputs: Union[Dict[str, Any], Any], return_only_outputs: bool = False, callbacks: Optional[Union[List[BaseCallbackHandler], BaseCallbackManager]] = None, *, tags: Optional[List[str]] = None, metadata: Optional[Dict[str, Any]] = None, run_name: Optional[str] = None, include_run_info: bool = False) → Dict[str, Any]¶
Asynchronously execute the chain.
Parameters
inputs – Dictionary of inputs, or single input if chain expects
only one param. Should contain all inputs specified in
Chain.input_keys except for inputs that will be set by the chain’s
memory.
return_only_outputs – Whether to return only outputs in the
response. If True, only new keys generated by this chain will be
returned. If False, both input keys and new keys generated by this
chain will be returned. Defaults to False.
callbacks – Callbacks to use for this chain run. These will be called in
addition to callbacks passed to the chain during construction, but only
these runtime callbacks will propagate to calls to other objects.
tags – List of string tags to pass to all callbacks. These will be passed in
addition to tags passed to the chain during construction, but only
exclude – fields to exclude from new model, as with values this takes precedence over include
update – values to change/add in the new model. Note: the data is not validated before creating
the new model: you should trust this data
deep – set to True to make a deep copy of the model
Returns
new model instance
dict(**kwargs: Any) → Dict¶
Dictionary representation of chain.
Expects Chain._chain_type property to be implemented and for memory to benull.
Parameters
**kwargs – Keyword arguments passed to default pydantic.BaseModel.dict
method.
Returns
A dictionary representation of the chain.
Example
chain.dict(exclude_unset=True)
# -> {"_type": "foo", "verbose": False, ...}
classmethod from_llm(llm: BaseLanguageModel, retriever: BaseRetriever, condense_question_prompt: BasePromptTemplate = PromptTemplate(input_variables=['chat_history', 'question'], template='Given the following conversation and a follow up question, rephrase the follow up question to be a standalone question, in its original language.\n\nChat History:\n{chat_history}\nFollow Up Input: {question}\nStandalone question:'), chain_type: str = 'stuff', verbose: bool = False, condense_question_llm: Optional[BaseLanguageModel] = None, combine_docs_chain_kwargs: Optional[Dict] = None, callbacks: Optional[Union[List[BaseCallbackHandler], BaseCallbackManager]] = None, **kwargs: Any) → BaseConversationalRetrievalChain[source]¶
Convenience method to load chain from LLM and retriever.
This provides some logic to create the question_generator chain
as well as the combine_docs_chain.
Parameters
llm – The default language model to use at every part of this chain
(eg in both the question generation and the answering)
(eg in both the question generation and the answering)
retriever – The retriever to use to fetch relevant documents from.
condense_question_prompt – The prompt to use to condense the chat history
and new question into a standalone question.
chain_type – The chain type to use to create the combine_docs_chain, will
be sent to load_qa_chain.
verbose – Verbosity flag for logging to stdout.
condense_question_llm – The language model to use for condensing the chat
history and new question into a standalone question. If none is
provided, will default to llm.
combine_docs_chain_kwargs – Parameters to pass as kwargs to load_qa_chain
when constructing the combine_docs_chain.
callbacks – Callbacks to pass to all subchains.
**kwargs – Additional parameters to pass when initializing
ConversationalRetrievalChain
classmethod from_orm(obj: Any) → Model¶
get_input_schema(config: Optional[RunnableConfig] = None) → Type[BaseModel]¶
Get a pydantic model that can be used to validate input to the runnable.
Runnables that leverage the configurable_fields and configurable_alternatives
methods will have a dynamic input schema that depends on which
configuration the runnable is invoked with.
This method allows to get an input schema for a specific configuration.
Parameters
config – A config to use when generating the schema.
Returns
A pydantic model that can be used to validate input.
classmethod get_lc_namespace() → List[str]¶
Get the namespace of the langchain object.
For example, if the class is langchain.llms.openai.OpenAI, then the
namespace is [“langchain”, “llms”, “openai”]
get_output_schema(config: Optional[RunnableConfig] = None) → Type[BaseModel]¶
Get a pydantic model that can be used to validate output to the runnable.
Runnables that leverage the configurable_fields and configurable_alternatives
methods will have a dynamic output schema that depends on which
configuration the runnable is invoked with.
This method allows to get an output schema for a specific configuration.
Parameters
config – A config to use when generating the schema.
Returns
A pydantic model that can be used to validate output.
invoke(input: Dict[str, Any], config: Optional[RunnableConfig] = None, **kwargs: Any) → Dict[str, Any]¶
Transform a single input into an output. Override to implement.
Parameters
input – The input to the runnable.
config – A config to use when invoking the runnable.
The config supports standard keys like ‘tags’, ‘metadata’ for tracing
purposes, ‘max_concurrency’ for controlling how much work to do
in parallel, and other keys. Please refer to the RunnableConfig
for more details.
Returns
The output of the runnable.
classmethod is_lc_serializable() → bool¶
Is this class serializable?
json(*, include: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, exclude: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, by_alias: bool = False, skip_defaults: Optional[bool] = None, exclude_unset: bool = False, exclude_defaults: bool = False, exclude_none: bool = False, encoder: Optional[Callable[[Any], Any]] = None, models_as_dict: bool = True, **dumps_kwargs: Any) → unicode¶
Generate a JSON representation of the model, include and exclude arguments as per dict().
encoder is an optional function to supply as default to json.dumps(), other arguments as per json.dumps().
classmethod lc_id() → List[str]¶
classmethod lc_id() → List[str]¶
A unique identifier for this class for serialization purposes.
The unique identifier is a list of strings that describes the path
to the object.
map() → Runnable[List[Input], List[Output]]¶
Return a new Runnable that maps a list of inputs to a list of outputs,
by calling invoke() with each input.
classmethod parse_file(path: Union[str, Path], *, content_type: unicode = None, encoding: unicode = 'utf8', proto: Protocol = None, allow_pickle: bool = False) → Model¶
classmethod parse_obj(obj: Any) → Model¶
classmethod parse_raw(b: Union[str, bytes], *, content_type: unicode = None, encoding: unicode = 'utf8', proto: Protocol = None, allow_pickle: bool = False) → Model¶
prep_inputs(inputs: Union[Dict[str, Any], Any]) → Dict[str, str]¶
Validate and prepare chain inputs, including adding inputs from memory.
Parameters
inputs – Dictionary of raw inputs, or single input if chain expects
only one param. Should contain all inputs specified in
Chain.input_keys except for inputs that will be set by the chain’s
memory.
Returns
A dictionary of all inputs, including those added by the chain’s memory.
prep_outputs(inputs: Dict[str, str], outputs: Dict[str, str], return_only_outputs: bool = False) → Dict[str, str]¶
Validate and prepare chain outputs, and save info about this run to memory.
Parameters
inputs – Dictionary of chain inputs, including any inputs added by chain
memory.
outputs – Dictionary of initial chain outputs.
return_only_outputs – Whether to only return the chain outputs. If False,
inputs are also added to the final outputs.
Returns
A dict of the final chain outputs.
Bind input and output types to a Runnable, returning a new Runnable.
property InputType: Type[langchain_core.runnables.utils.Input]¶
The type of input this runnable accepts specified as a type annotation.
property OutputType: Type[langchain_core.runnables.utils.Output]¶
The type of output this runnable produces specified as a type annotation.
property config_specs: List[langchain_core.runnables.utils.ConfigurableFieldSpec]¶
List configurable fields for this runnable.
property input_keys: List[str]¶
Input keys.
property input_schema: Type[pydantic.main.BaseModel]¶
The type of input this runnable accepts specified as a pydantic model.
property lc_attributes: Dict¶
List of attribute names that should be included in the serialized kwargs.
These attributes must be accepted by the constructor.
property lc_secrets: Dict[str, str]¶
A map of constructor argument names to secret ids.
For example,{“openai_api_key”: “OPENAI_API_KEY”}
property output_schema: Type[pydantic.main.BaseModel]¶
The type of output this runnable produces specified as a pydantic model.
Examples using ConversationalRetrievalChain¶
Wikipedia
Arxiv
Chat Over Documents with Vectara
Vectara
Set env var OPENAI_API_KEY or load from a .env file:
Set env var OPENAI_API_KEY or load from a .env file
Analysis of Twitter the-algorithm source code with LangChain, GPT4 and Activeloop’s Deep Lake
Use LangChain, GPT and Activeloop’s Deep Lake to work with code base
Structure answers with OpenAI functions
QA using Activeloop’s DeepLake
langchain.chains.query_constructor.ir.Expr¶
class langchain.chains.query_constructor.ir.Expr[source]¶
Bases: BaseModel
Base class for all expressions.
Create a new model by parsing and validating input data from keyword arguments.
Raises ValidationError if the input data cannot be parsed to form a valid model.
accept(visitor: Visitor) → Any[source]¶
Accept a visitor.
Parameters
visitor – visitor to accept
Returns
result of visiting
classmethod construct(_fields_set: Optional[SetStr] = None, **values: Any) → Model¶
Creates a new model setting __dict__ and __fields_set__ from trusted or pre-validated data.
Default values are respected, but no other validation is performed.
Behaves as if Config.extra = ‘allow’ was set since it adds all passed values
copy(*, include: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, exclude: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, update: Optional[DictStrAny] = None, deep: bool = False) → Model¶
Duplicate a model, optionally choose which fields to include, exclude and change.
Parameters
include – fields to include in new model
exclude – fields to exclude from new model, as with values this takes precedence over include
update – values to change/add in the new model. Note: the data is not validated before creating
the new model: you should trust this data
deep – set to True to make a deep copy of the model
Returns
new model instance
langchain.chains.conversational_retrieval.base.InputType¶
class langchain.chains.conversational_retrieval.base.InputType[source]¶
Bases: BaseModel
Create a new model by parsing and validating input data from keyword arguments.
Raises ValidationError if the input data cannot be parsed to form a valid model.
param chat_history: List[Union[Tuple[str, str], langchain_core.messages.base.BaseMessage]] [Optional]¶
param question: str [Required]¶
classmethod construct(_fields_set: Optional[SetStr] = None, **values: Any) → Model¶
Creates a new model setting __dict__ and __fields_set__ from trusted or pre-validated data.
Default values are respected, but no other validation is performed.
Behaves as if Config.extra = ‘allow’ was set since it adds all passed values
copy(*, include: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, exclude: Optional[Union[AbstractSetIntStr, MappingIntStrAny]] = None, update: Optional[DictStrAny] = None, deep: bool = False) → Model¶
Duplicate a model, optionally choose which fields to include, exclude and change.
Parameters
include – fields to include in new model
exclude – fields to exclude from new model, as with values this takes precedence over include
update – values to change/add in the new model. Note: the data is not validated before creating
the new model: you should trust this data
deep – set to True to make a deep copy of the model
Returns
new model instance
langchain.chains.ernie_functions.base.create_structured_output_runnable¶
langchain.chains.ernie_functions.base.create_structured_output_runnable(output_schema: Union[Dict[str, Any], Type[BaseModel]], llm: Runnable, prompt: BasePromptTemplate, *, output_parser: Optional[Union[BaseOutputParser, BaseGenerationOutputParser]] = None, **kwargs: Any) → Runnable[source]¶
Create a runnable that uses an Ernie function to get a structured output.
Parameters
output_schema – Either a dictionary or pydantic.BaseModel class. If a dictionary
is passed in, it’s assumed to already be a valid JsonSchema.
For best results, pydantic.BaseModels should have docstrings describing what
the schema represents and descriptions for the parameters.
llm – Language model to use, assumed to support the Ernie function-calling API.
prompt – BasePromptTemplate to pass to the model.
output_parser – BaseLLMOutputParser to use for parsing model outputs. By default
will be inferred from the function types. If pydantic.BaseModels are passed
in, then the OutputParser will try to parse outputs using those. Otherwise
model outputs will simply be parsed as JSON.
Returns
A runnable sequence that will pass the given function to the model when run.
Example
from typing import Optional
from langchain.chains.ernie_functions import create_structured_output_chain
from langchain.chat_models import ErnieBotChat
from langchain.prompts import ChatPromptTemplate
from langchain.pydantic_v1 import BaseModel, Field
class Dog(BaseModel):
    """Identifying information about a dog."""
    name: str = Field(..., description="The dog's name")
    color: str = Field(..., description="The dog's color")
color: str = Field(..., description="The dog's color")
    fav_food: Optional[str] = Field(None, description="The dog's favorite food")
llm = ErnieBotChat(model_name="ERNIE-Bot-4")
prompt = ChatPromptTemplate.from_messages(
    [
        ("user", "Use the given format to extract information from the following input: {input}"),
        ("assistant", "OK!"),
        ("user", "Tip: Make sure to answer in the correct format"),
    ]
)
chain = create_structured_output_chain(Dog, llm, prompt)
chain.invoke({"input": "Harry was a chubby brown beagle who loved chicken"})
# -> Dog(name="Harry", color="brown", fav_food="chicken")
langchain.chains.ernie_functions.base.convert_python_function_to_ernie_function¶
langchain.chains.ernie_functions.base.convert_python_function_to_ernie_function(function: Callable) → Dict[str, Any][source]¶
Convert a Python function to an Ernie function-calling API compatible dict.
Assumes the Python function has type hints and a docstring with a description. Ifthe docstring has Google Python style argument descriptions, these will be
included as well.