For our water quality assurance task, we need to write a regular expression to extract specific values from a response JSON. For more info please look at [^regular-expressions.pdf]

For starting, please extract the `turbidity-fnu` values.
Example JSON response: https://gltg-dev.ncsa.illinois.edu/clowder/api/geostreams/datapoints?sensor_id=4171
Regex tester: http://regexstorm.net/tester

Online tool: https://regexr.com/
Regular expression provided (not working yet): 

^.*?"end_time":"(?\d{4})-(?\d{2})-(?\d{2})T(?\d{2}:\d{2}:\d{2})Z".*?"turbidity-fnu":(?[\d.]+)