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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 cuboid(target, throat_length='throat.length', throat_diameter='throat.diameter'):
 r""" Calculate throat volume assuing a square cross-section Parameters target : OpenPNM Object The object which this model is associated with. This controls the length of the calculated array, and also provides access to other necessary properties. throat_length and throat_diameter : strings The dictionary keys containing the arrays with the throat diameter and length values. Notes ----- At present this models does NOT account for the volume reprsented by the intersection of the throat with a spherical pore body. """

    leng = target[throat_length]
    diam = target[throat_diameter]
    value = leng*diam**2
    return value