Google has a single SDK to control and interact with all its cloud infrastructure services and APIs. Unfortunately, the way it installs some Python libraries, like that for the App Engine standard environment, is completely baffling. If you didn't know there were more than one kind of App Engine, well that's a whole different problem.
To install the Python packages that lets you interact with the App Engine, the documentation instructs you do install the Cloud SDK then run the following command
gcloud components install app-engine-python
Okay, great that was easy. Now open up the interpreter and you realize its not importable. So where is it?
It turns out that the App Engine package was installed in the folder where the Cloud SDK is, not in the current interpreter's site-packages directory. So if your Cloud SDK folder is in /Users/me/google-cloud-sdk, then the google package will be in /Users/me/google-cloud-sdk/platform/google_appengine/google where "google" is the package folder.
Now how do you make this work nicely with conda?
Let's say you installed Anaconda/Miniconda in /Users/me/miniconda. If you have a Python 2.7 conda environment named appengine, its Python site-packages should be located in /Users/you/miniconda/envs/appengine/lib/python2.7/site-packages.
The easiest way to make the App Engine SDK importable when running your appengine environment is to connect them using a symlink like so
ln -s <path-to-google-cloud-sdk>/platform/google_appengine/google <path-to-conda>/envs/<env-name>/lib/python2.7/site-packages/google
where <path-to-google-cloud-sdk> is the location where you installed Cloud SDK, <path-to-conda> is the location where Anaconda/Miniconda was installed, and <env-name> is the name of your target environment.