Fix for name of collection being a tuple (aws#242)

* Fix tuple going in as name of coll

* Add xgboost to CI

* Install xgboost

Author: rahul003

config/buildspec.yml

@@ -6,6 +6,7 @@ env:
     run_pytest_pytorch: "enable"
     run_pytest_mxnet: "enable"
     run_pytest_tensorflow: "enable"
+    run_pytest_xgboost: "enable"
 phases:
   install:
     commands:
@@ -15,7 +16,7 @@ phases:
         - sudo apt-get update
         - sudo apt-get install unzip
         - cd $CODEBUILD_SRC_DIR  && chmod +x config/protoc_downloader.sh && ./config/protoc_downloader.sh
-        - pip install pytest wheel pyYaml pytest-html tensorflow mxnet torch
+        - pip install pytest wheel pyYaml pytest-html tensorflow mxnet torch xgboost
         - pip uninstall -y boto3 && pip uninstall -y aiobotocore && pip uninstall -y botocore
 
   pre_build:

tornasole/core/collection.py

@@ -24,10 +24,10 @@ class CollectionKeys:
   HISTOGRAMS = 'histograms'
 
   #XGBOOST
-  METRIC = "metric",
-  PREDICTIONS = "predictions",
-  LABELS = "labels",
-  FEATURE_IMPORTANCE = "feature_importance",
+  METRIC = "metric"
+  PREDICTIONS = "predictions"
+  LABELS = "labels"
+  FEATURE_IMPORTANCE = "feature_importance"
   AVERAGE_SHAP = "average_shap"