Average Rating, Skipping Gaps

A film festival collects audience ratings in a CSV file. Not everyone rated every film, so some cells are empty.

Task: write average_of(path, text, column_name). It returns the average of the numbers in the column called column_name, as a float.

• An empty value ("") means "no rating". Leave it out completely, so it doesn't count as 0 and isn't part of the count.
• Every other value in that column is a number, possibly with a decimal point.
• If there are no ratings to average, return 0.0.
• The column always exists, but it can be anywhere in the row.

The starter code includes a small helper, write_text, and already calls it for you: it saves text into a file named path. Your code then opens that file and reads it. import csv is already at the top of the starter code.