human
I am working on the file "Sessions/Session03/Day2/OOP.ipynb".
The first task is:
Problem 1) Create a galaxy class
We will begin our experience with object-oriented code by creating a class to represent a galaxy.  In order to do this, we must define the class, give it some default methods, and then define some attributes to describe each instance of a galaxy.
Problem 1a
What do you think should be the attributes and characteristics that should be tracked for a galaxy object?  Think critically and make a list of at least six different quantities that would make sense if this were a research project.  Please do this prior to starting (or looking at) the example below. Discuss with your code partner.
Provide your answer to Problem 1a here
Problem 1b
Define a galaxy class, and give it an initializer class method.  Have your initializer accept arguments for total_mass, cold_gas_mass, and stellar_mass.  Have it also accept keyword arguments for age with a default set to 0.  Maybe also include a SFR and color in your attributes, but initialize it to 0 and 'red' respectively.  I'll include docstrings for you to help guide you along the way.
Hint: Don't forget to use self to indicate an object of this class.
Can you write Python code for it?
 Here do you think should be the attributes and characteristics that should be tracked for a galaxy object?
assistant
#Here do you think should be the attributes and characteristics that should be tracked for a galaxy object.

class Galaxy():
    """
    Galaxy class for simply representing a galaxy.
    """
    def __init__( #complete