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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 standard(target, mol_weight='pore.molecular_weight', density='pore.density'):
 r""" Calculates the molar density from the molecular weight and mass density Parameters target : OpenPNM Object The object for which these values are being calculated. This controls the length of the calculated array, and also provides access to other necessary thermofluid properties. pore_MW : string The dictionary key containing the molecular weight in kg/mol pore_temperature : string The dictionary key containing the density in kg/m3 """

    MW = target[mol_weight]
    rho = target[density]
    value = rho/MW
    return value