This is also a simplified version of an exercise found in "The Melodic Minor Handbook" by yours truly and published by Jamey Aebersold. The exercise in the book consists a 4 bar minor ii-V7-i using 3 different Melodic Minor scales. Both exercises are "continuous scale' types, where the inherent first note of each new scale picks up where the last note of the previous one left off.
For example: measure #1, (D- = D Mel. Min. = D-E-F-G-A-B-C#-D).
measure #2, (A7alt = Bb Mel. Min = Eb-F-G-A-Bb-C-Db-Eb)
measure #3, (D- = D Mel. Min. = E-F-G-A-B-C#-D-E).
And so on. Get the drift?