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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 virtual_potential_temperature(pressure, temperature, mixing, molecular_weight_ratio=mpconsts.epsilon):
 r"""Calculate virtual potential temperature. This calculation must be given an air parcel's pressure, temperature, and mixing ratio. The implementation uses the formula outlined in [Markowski2010]_ pg.13. Parameters pressure: `pint.Quantity` Total atmospheric pressure temperature: `pint.Quantity` The temperature 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 virtual potential temperature of the parcel Notes ----- .. math:: \Theta_v = \Theta \frac{\text{w} + \epsilon}{\epsilon\,(1 + \text{w})} """

    pottemp = potential_temperature(pressure, temperature)
    return virtual_temperature(pottemp, mixing, molecular_weight_ratio)