human
I am working on the file "Sessions/Session03/Day2/OOP.ipynb".
The first task is:
Problem 2f
Based on your knowledge of how galaxies evolve, do these results make sense?  Discuss with your coding partner if so/not, and ways in which you might tweak it to work better.
Provide your answer to Problem 2f here
Problem 3) Make a galaxy class that can interact with other galaxies (challenging!)
Most galaxies do not evolve in isolation, so let's make a galaxy class that enables galaxies to actually interact with each other.  We can re-use much of the code from our previous examples through inheritance!  Yeah!
Problem 3a
Let us create a new subclass of EvolveGalaxy, so that it inherits most of the traits of our previous work.  But we will add some new features including position and velocity values in the x-y plane, so that our galaxy can actually move over time.
Create a new class MovingGalaxy that is a subclass of EvolveGalaxy.  Make a new __init__ method with all of the arguments from it's parent class EvolveGalaxy, but add the additional arguments of x_position, y_position, x_velocity, y_velocity, and id_num.  
Note: all arguments must come before any keyword arguments, so the age kwarg has to come at the very end.
Also, make a new __repr__ method for this class that just includes it's idnum, x_position, and y_position.
To assure your code works, create an instance of a MovingGalaxy, and print it out.
Can you write Python code for it?
assistant
#Here is Python code to print it out.

class MovingGalaxy(EvolvingGalaxy):
    """
    Galaxy class that can evolve and move in the x,y plane
    """
    def __init__(self, total_mass, cold_gas_mass, stellar_mass, #complete
        
        # Replace self with super to activate the superclass's methods
        super().__init__(total_mass, cold_gas_mass, stellar_mass)
        
        #complete
        
    def __repr__(self):
        #complete

#complete