AshGDS

1. run sudo pip3 install grpcio -i https://www.piwheels.hostedpi.com/simple - This will download a prebuilt version of grpcio for Pi's (and bypassed the error i had)

2. create a requirements.txt file and paste this into that txt file: grpcio>=1.18.0

3. run sudo pip3 install firebase-admin -r requirements.txt

If you're having issues try sudo pip3 install firebase-admin -i https://www.piwheels.hostedpi.com/simple aswell

AshGDS

tools.get_a_json()
        .then(function (returned_json) {
          assert.ok(!returned_json["value_that_is_true"]);       
          done()
        })
        .catch(function (err) {
          done(err)
        });