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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def density(pressure, temperature, mixing, molecular_weight_ratio=mpconsts.epsilon):
 r"""Calculate density. This calculation must be given an air parcel's pressure, temperature, and mixing ratio. The implementation uses the formula outlined in [Hobbs2006]_ pg.67. Parameters temperature: `pint.Quantity` The temperature pressure: `pint.Quantity` Total atmospheric pressure mixing : `pint.Quantity` dimensionless mass mixing ratio molecular_weight_ratio : `pint.Quantity` or float, optional The ratio of the molecular weight of the constituent gas to that assumed for air. Defaults to the ratio for water vapor to dry air. (:math:`\epsilon\approx0.622`). Returns ------- `pint.Quantity` The corresponding density of the parcel Notes ----- .. math:: \rho = \frac{p}{R_dT_v} """

    virttemp = virtual_temperature(temperature, mixing, molecular_weight_ratio)
    return (pressure / (mpconsts.Rd * virttemp)).to(units.kilogram / units.meter ** 3)