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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 brock_bird_scaling(target, sigma_o, To, temperature='pore.temperature', critical_temperature='pore.critical_temperature'):
 r""" Uses Brock_Bird model to adjust surface tension from it's value at a given reference temperature to temperature 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. To : float Reference temperature (K) sigma_o : float Surface tension at reference temperature (N/m) temperature : string The dictionary key containing the temperature values (K) critical_temperature : string The dictionary key containing the critical temperature values (K) """

    Tc = target[critical_temperature]
    Ti = target[temperature]
    Tro = To/Tc
    Tri = Ti/Tc
    value = sigma_o*(1-Tri)**(11/9)/(1-Tro)**(11/9)
    return value