Install CDP client after Python on macOS

Install the CDP CLI client and verify the installation.

Use the following command to install the CDP client:
```
$ pip3 install cdpcli --user
```
Check the location of your Python directory that contains the client executable files. For example, for Python 3.6.x the executable files are in the following directory:
```
~/Library/Python/3.6/bin
```
Add the Python directory that contains the client executable files to the PATH environment variable.
For example:
```
echo "~/Library/Python/3.6/bin" | sudo tee -a /etc/paths
```
Use the following command to verify that the CDP client is correctly installed:
```
cdp --version
```
To upgrade the CDP client to the latest version, run the following command:
```
$ pip3 install cdpcli --upgrade --user
```