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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 particle_number_concentration(ConcMat, material):
 """Return the number of particles in suspension. :param ConcMat: Concentration of the material :type ConcMat: float :param material: The material in solution :type material: floc_model.Material """

    return ConcMat.to(material.Density.units) / ((material.Density * np.pi * material.Diameter**3) / 6)