### Summary
Adds a new document loader for processing e-publications. Works with
`unstructured>=0.5.4`. You need to have
[`pandoc`](https://pandoc.org/installing.html) installed for this loader
to work.
### Testing
```python
from langchain.document_loaders import UnstructuredEPubLoader
loader = UnstructuredEPubLoader("winter-sports.epub", mode="elements")
data = loader.load()
data[0]
```
- Current docs are pointing to the wrong module, fixed
- Added some explanation on how to find the necessary parameters
- Added chat-based codegen example w/ retrievers
Picture of the new page:

Please let me know if you'd like any tweaks! I wasn't sure if the
example was too heavy for the page or not but decided "hey, I probably
would want to see it" and so included it.
Co-authored-by: maxtheman <max@maxs-mbp.lan>
@3coins + @zoltan-fedor.... heres the pr + some minor changes i made.
thoguhts? can try to get it into tmrws release
---------
Co-authored-by: Zoltan Fedor <zoltan.0.fedor@gmail.com>
Co-authored-by: Piyush Jain <piyushjain@duck.com>
I've found it useful to track the number of successful requests to
OpenAI. This gives me a better sense of the efficiency of my prompts and
helps compare map_reduce/refine on a cheaper model vs. stuffing on a
more expensive model with higher capacity.
This PR adds Notion DB loader for langchain.
It reads content from pages within a Notion Database. It uses the Notion
API to query the database and read the pages. It also reads the metadata
from the pages and stores it in the Document object.
seems linkchecker isn't catching them because it runs on generated html.
at that point the links are already missing.
the generation process seems to strip invalid references when they can't
be re-written from md to html.
I used https://github.com/tcort/markdown-link-check to check the doc
source directly.
There are a few false positives on localhost for development.
Added support for document loaders for Azure Blob Storage using a
connection string. Fixes#1805
---------
Co-authored-by: Mick Vleeshouwer <mick@imick.nl>
Ran into a broken build if bs4 wasn't installed in the project.
Minor tweak to follow the other doc loaders optional package-loading
conventions.
Also updated html docs to include reference to this new html loader.
side note: Should there be 2 different html-to-text document loaders?
This new one only handles local files, while the existing unstructured
html loader handles HTML from local and remote. So it seems like the
improvement was adding the title to the metadata, which is useful but
could also be added to `html.py`
In https://github.com/hwchase17/langchain/issues/1716 , it was
identified that there were two .py files performing similar tasks. As a
resolution, one of the files has been removed, as its purpose had
already been fulfilled by the other file. Additionally, the init has
been updated accordingly.
Furthermore, the how_to_guides.rst file has been updated to include
links to documentation that was previously missing. This was deemed
necessary as the existing list on
https://langchain.readthedocs.io/en/latest/modules/document_loaders/how_to_guides.html
was incomplete, causing confusion for users who rely on the full list of
documentation on the left sidebar of the website.