make default installation faster (#2)

* remove cohere as default

* refractor dependencies

* use llama-index pdf reader as default (pypdf)

* fix some lazy docstring

* update install scripts

* minor fix

libs/ktem/ktem/index/file/pipelines.py

@@ -25,7 +25,7 @@ from theflow.utils.modules import import_dotted_string
 from kotaemon.base import RetrievedDocument
 from kotaemon.indices import VectorIndexing, VectorRetrieval
 from kotaemon.indices.ingests import DocumentIngestor
-from kotaemon.indices.rankings import BaseReranking, CohereReranking, LLMReranking
+from kotaemon.indices.rankings import BaseReranking, LLMReranking
 
 from .base import BaseFileIndexIndexing, BaseFileIndexRetriever
 
@@ -67,9 +67,7 @@ class DocumentRetrievalPipeline(BaseFileIndexRetriever):
     vector_retrieval: VectorRetrieval = VectorRetrieval.withx(
         embedding=embeddings.get_default(),
     )
-    reranker: BaseReranking = CohereReranking.withx(
-        cohere_api_key=getattr(settings, "COHERE_API_KEY", "")
-    ) >> LLMReranking.withx(llm=llms.get_lowest_cost())
+    reranker: BaseReranking = LLMReranking.withx(llm=llms.get_lowest_cost())
     get_extra_table: bool = False
 
     def run(

libs/ktem/pyproject.toml

@@ -13,18 +13,14 @@ version = "0.2.0"
 requires-python = ">= 3.10"
 description = "RAG-based Question and Answering Application"
 dependencies = [
-    "chromadb",
     "click",
-    "cohere",
     "platformdirs",
     "pluggy",
     "python-decouple",
-    "python-dotenv",
     "python-pptx",
     "sqlalchemy",
     "sqlmodel",
     "tiktoken",
-    "unstructured[pdf]",
 ]
 readme = "README.md"
 license = { text = "MIT License" }