Missing import and typo in "Instruments to Measure Golden Signals"

mhite

re:

https://trainingportal.linuxfoundation.org/learn/course/getting-started-with-opentelemetry-lfs148/hands-on-lab-manual-instrumentation-metrics/instruments-to-measure-golden-signals?page=7

Need at add:

from opentelemetry.metrics import Histogram

Also, histrogram_explicit_buckets should probably be renamed to histogram_explicit_buckets.

The section where it says:

metric_utils.py
# adjust aggregation of an instrument

... seems like you should probably mention this goes into create_views() function.

Also, at the very end, it's good if you run some ab against the API endpoint to have the histogram metrics get output to the console.