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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 dens_alum_nanocluster(coag):
 """Return the density of the aluminum in the nanocluster. This is useful for determining the volume of nanoclusters given a concentration of aluminum. """

    density = (coag.PrecipDensity * MOLEC_WEIGHT_ALUMINUM
               * coag.PrecipAluminumMPM / coag.PrecipMolecWeight)
    return density