updating readme about the commandline

Author: seperman

README.md

@@ -27,6 +27,10 @@ Tested on Python 3.6+ and PyPy3.
 
 `pip install deepdiff`
 
+If you want to use DeepDiff from commandline:
+
+`pip install "deepdiff[cli]"`
+
 ### Importing
 
 ```python
@@ -35,13 +39,24 @@ Tested on Python 3.6+ and PyPy3.
 >>> from deepdiff import DeepHash  # For hashing objects based on their contents
 ```
 
+Note: if you want to use DeepDiff via commandline, make sure to run `pip install "deepdiff[cli]"`. Then you can access the commands via:
+
+- DeepDiff
+    - `$ deep diff --help`
+- Delta
+    - `$ deep patch --help`
+- grep
+    - `$ deep grep --help`
+- extract
+    - `$ deep extract --help`
+
 # Deep Diff
 
 DeepDiff gets the difference of 2 objects.
 
 > - Please take a look at the [DeepDiff docs](https://zepworks.com/deepdiff/5.2.1/diff.html)
-> - The full documentation can be found on <https://zepworks.com/deepdiff/5.2.1/>
-> - Tutorials can be found on <https://zepworks.com/tags/deepdiff/>
+> - The full documentation of all modules can be found on <https://zepworks.com/deepdiff/5.2.1/>
+> - Tutorials and posts about DeepDiff can be found on <https://zepworks.com/tags/deepdiff/>
 
 ## A few Examples
 

deepdiff/diff.py

@@ -382,6 +382,7 @@ def _skip_this(self, level):
         Check whether this comparison should be skipped because one of the objects to compare meets exclusion criteria.
         :rtype: bool
         """
+        print(f"skip? {level.path()}")
         skip = False
         if self.exclude_paths and level.path() in self.exclude_paths:
             skip = True

docs/index.rst

@@ -31,7 +31,7 @@ The DeepDiff library includes the following modules:
 Supported Python Versions
 *************************
 
-DeepDiff is rigorously tested against Python 3.5, 3.6, 3.7, 3.8 and Pypy3
+DeepDiff is rigorously tested against Python 3.6, 3.7, 3.8, 3.9 and Pypy3
 
 NOTE: Python 2 is not supported any more. DeepDiff v3.3.0 was the last version to supprt Python 2.
 
@@ -49,6 +49,10 @@ Install from PyPi::
 
     pip install deepdiff
 
+If you want to use DeepDiff from commandline::
+
+    pip install "deepdiff[cli]"
+
 Read about DeepDiff optimizations at :ref:`optimizations_label`
 
 
@@ -64,6 +68,20 @@ Importing
     >>> from deepdiff import extract  # For extracting a path from an object
 
 
+Note: if you want to use DeepDiff via commandline, make sure to run:: 
+    pip install "deepdiff[cli]"
+
+Then you can access the commands via:
+
+- DeepDiff::
+    $ deep diff --help
+- Delta::
+    $ deep patch --help
+- grep::
+    $ deep grep --help
+- extract::
+    $ deep extract --help
+
 Supported data types
 ~~~~~~~~~~~~~~~~~~~~