<commit_before># Documents
The Document Registry is the default mechanism for interacting with
files in JupyterLab.  The Document Manager uses it to create models and 
widgets for documents.  The File Browser uses the Document Manager when 
creating and opening files.

The Document Manager handles models, contexts, and widgets for documents 
and manages their life cycle.

Extensions in the JupyterLab application can register widget factories, 
model factories, widget extensions, file types, and file creators.

## Widget factories 
Create a widget for a given file. An example is the notebook widget 
factory that creates NotebookPanel widgets.

## Model factories 
Create a model for a given file.  Models are generally differentiated by 
the contents options used to fetch the model (e.g. text, base64, notebook).

## Widget extensions
Add additional functionality to a widget. An extension instance is created 
for each widget.  An example is the ipywidgets extension that is created 
for NotebookPanel widgets.  Another example would be to add a button to the 
toolbar of each NotebookPanel widget.

## File types 
Intended to be used in a "Create New" dialog, providing a list of known 
file types.

## File creators 
Intended for create quick launch file creators. The default use will be for <commit_msg>Capitalization<commit_after># Documents
The Document Registry is the default mechanism for interacting with
files in JupyterLab.  The Document Manager uses it to create models and 
widgets for documents.  The File Browser uses the Document Manager when 
creating and opening files.

The Document Manager handles models, contexts, and widgets for documents 
and manages their life cycle.

Extensions in the JupyterLab application can register widget factories, 
model factories, widget extensions, file types, and file creators.

## Widget Factories 
Create a widget for a given file. An example is the notebook widget 
factory that creates NotebookPanel widgets.

## Model Factories 
Create a model for a given file.  Models are generally differentiated by 
the contents options used to fetch the model (e.g. text, base64, notebook).

## Widget Extensions
Add additional functionality to a widget. An extension instance is created 
for each widget.  An example is the ipywidgets extension that is created 
for NotebookPanel widgets.  Another example would be to add a button to the 
toolbar of each NotebookPanel widget.

## File Types 
Intended to be used in a "Create New" dialog, providing a list of known 
file types.

## File Creators 
Intended for create quick launch file creators. The default use will be for 
{'fraction_non_alphanumeric': 0.03342195214584125, 'fraction_numerical': 0.0015191796429927839, 'mean_word_length': 4.430927835051547, 'pattern_counts': {'":': 0, '<': 3, '<?xml version=': 0, '>': 3, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
{'dir': 'git-commits-cleaned', 'id': '3789353', 'n_tokens_mistral': 667, 'n_tokens_neox': 631, 'n_words': 388}