fix: dependencies (#416)

pyproject.toml

@@ -91,6 +91,10 @@ beautifulsoup4 = "^4.12.2"
 pypdf = "^3.11.0"
 pytube = "^15.0.0"
 llama-index = { version = "^0.7.21", optional = true }
+sentence-transformers = { version = "^2.2.2", optional = true }
+torch = { version = ">=2.0.0, !=2.0.1", optional = true }
+# Torch 2.0.1 is not compatible with poetry (https://github.com/pytorch/pytorch/issues/100974)
+gpt4all = { version = "^1.0.8", optional = true }
 elasticsearch = { version = "^8.9.0", optional = true }
 flask = "^2.3.3"
 twilio = "^8.5.0"
@@ -110,6 +114,7 @@ isort = "^5.12.0"
 [tool.poetry.extras]
 streamlit = ["streamlit"]
 community = ["llama-index"]
+opensource = ["sentence-transformers", "torch", "gpt4all"]
 elasticsearch = ["elasticsearch"]
 
 [tool.poetry.group.docs.dependencies]