Proper way of constructing and displaying quantities using Astropy in Jupyter Notebooks

astropy_quantities.py

# Science
import numpy as np
from astropy.units import Unit

# Notebook
from IPython.display import Markdown
from IPython.core.interactiveshell import InteractiveShell
InteractiveShell.ast_node_interactivity = "all"

# Handy functions
def Qshow(Q, sigfig=2, unit=None, name=None):
    name = Q.info.name
    if unit is not None:
        Q = Q.to(unit)
    if sigfig is not None:
        q = Q.round(sigfig - int(np.log10(Q.value)))
    else:
        q = Q
    if name is not None:
        output = Markdown(f'{name} = {q._repr_latex_()}')
    else:
        output = Markdown(f'{q._repr_latex_()}')
    return output

# Parameter
density = 1.23456e12 * Unit('g/cm^3')
density.info.name = r'$\rho$'

# Results
Qshow(density)