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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 linear(target, m, b, prop):
 r""" Calculates a property as a linear function of a given property 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. m, b : floats Slope and intercept of the linear corelation prop : string The dictionary key containing the independent variable or phase property to be used in the correlation. """

    x = target[prop]
    value = m*x + b
    return value