update markdown formatting

Author: TimidRobot

README.md

@@ -39,20 +39,19 @@ modules:
 - macOS:
   1. Install [Homebrew][homebrew]
   2. Install pipenv:
-        ```
+        ```shell
         brew install pipenv
         ```
-  3. Create the Python virtual environment and install prerequisites using:
-       `pipenv`:
-       	```
-     	shell pipenv sync --dev
-    	``` 
-  4. Then you can run the static analysis tools:
+  3. Create the Python virtual environment and install prerequisites using
+     `pipenv`:
+        ```shell
+        pipenv sync --dev
         ```
-     	shell ./tools.sh
+  4. Then you can run the static analysis tools:
+        ```shell
+        ./tools.sh
         ```
 
-
 [pipenvdocs]: https://pipenv.pypa.io/en/latest/
 [homebrew]: https://brew.sh/
 [pipenvinstall]: https://pipenv.pypa.io/en/latest/install/#installing-pipenv
@@ -82,7 +81,7 @@ To successfully run scripts that require client credentials, you will need to fo
 - [flake8][flake8]: a python tool that glues together pep8, pyflakes, mccabe,
   and third-party plugins to check the style and quality of some python code.
 - [isort][isort]: A Python utility / library to sort imports
-	- It doesn't import any libraries, it only sorts and formats them. 
+  - (It doesn't import any libraries, it only sorts and formats them.)
 
 [ccospyguide]: https://opensource.creativecommons.org/contributing-code/python-guidelines/
 [black]: https://github.com/psf/black