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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 sato(target, mol_weight='pore.molecular_weight', boiling_temperature='pore.boiling_point', temperature='pore.temperature', critical_temperature='pore.critical_temperature'):
 r""" Uses Sato et al. model to estimate thermal conductivity for pure liquids from first principles at conditions of interest 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. boiling_temperature : string Dictionary key containing the toiling temperature of the component (K) mol_weight : string Dictionary key containing the molecular weight of the component (kg/mol) temperature : string The dictionary key containing the temperature values (K) critical_temperature : string The dictionary key containing the critical temperature values (K) """

    T = target[temperature]
    Tc = target[critical_temperature]
    MW = target[mol_weight]
    Tbr = target[boiling_temperature]/Tc
    Tr = T/Tc
    value = (1.11/((MW*1e3)**0.5))*(3+20*(1-Tr)**(2/3))/(3+20*(1-Tbr)**(2/3))
    return value