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Solve the following python programming problem given the following code:
# First, we need to know what's in the data file.

!head R11ceph.dat

class Cepheids(object):
    
    def __init__(self,filename):
        # Read in the data and store it in this master array:
        self.data = np.loadtxt(filename)
        self.hosts = self.data[:,1].astype('int').astype('str')
        # We'll need the plotting setup to be the same each time we make a plot:
        colornames = ['red','orange','yellow','green','cyan','blue','violet','magenta','gray']
        self.colors = dict(zip(self.list_hosts(), colornames))
        self.xlimits = np.array([0.3,2.3])
        self.ylimits = np.array([30.0,17.0])
        return
    
    def list_hosts(self):
        # The list of (9) unique galaxy host names:
        return np.unique(self.hosts)
    
    def select(self,ID):
        # Pull out one galaxy's data from the master array:
        index = (self.hosts == str(ID))
        self.m = self.data[index,2]
        self.merr = self.data[index,3]
        self.logP = np.log10(self.data[index,4])
        return
    
    def plot(self,X):
        # Plot all the points in the dataset for host galaxy X.
        ID = str(X)
        self.select(ID)
        plt.rc('xtick', labelsize=16) 
        plt.rc('ytick', labelsize=16)
        plt.errorbar(self.logP, self.m, yerr=self.merr, fmt='.', ms=7, lw=1, color=self.colors[ID], label='NGC'+ID)
        plt.xlabel('$\\log_{10} P / {\\rm days}$',fontsize=20)
        plt.ylabel('${\\rm magnitude (AB)}$',fontsize=20)
        plt.xlim(self.xlimits)
        plt.ylim(self.ylimits)
        plt.title('Cepheid Period-Luminosity (Riess et al 2011)',fontsize=20)
        return

    def overlay_straight_line_with(self,m=0.0,c=24.0):
        # Overlay a straight line with gradient m and intercept c.
        x = self.xlimits
        y = m*x + c
        plt.plot(x, y, 'k-', alpha=0.5, lw=2)
        plt.xlim(self.xlimits)
        plt.ylim(self.ylimits)
        return
    
    def add_legend(self):
        plt.legend(loc='upper left')
        return

C = Cepheids('R11ceph.dat')
print C.colors
Given the above code, generate some markdown instructions for it.
assistant
#Here is Python program to print C.

A Look at Each Host Galaxy's Cepheids
Let's read in all the data, and look at each galaxy's Cepheid measurements separately. Instead of using pandas, we'll write our own simple data structure, and give it a custom plotting method so we can compare the different host galaxies' datasets.