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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 prof_pressure(altitude, z_coef=(1.94170e-9, -5.14580e-7, 4.57018e-5, -1.55620e-3, -4.61994e-2, 2.99955)):
 """ Return pressure for given altitude. This function evaluates a polynomial at altitudes values. Parameters altitude : array-like altitude values [km]. z_coef : array-like coefficients of the polynomial (default values are for the US Standard Atmosphere). Returns ------- pressure : array-like pressure values [hPa] (same shape than the altitude input array). See Also -------- prof_altitude : Returns altitude for given pressure. prof_temperature : Returns air temperature for given altitude. Notes ----- Default coefficient values represent a 5th degree polynomial which had been fitted to USA data from 0-100 km. Accuracy is on the order of 1% for 0-100 km and 0.5% below 30 km. This function, with default values, may thus produce bad results with altitude > 100 km. Examples -------- array([ 998.96437334, 264.658697 , 55.28114631]) """

    altitude = np.asarray(altitude)
    pressure = np.power(10, np.polyval(z_coef, altitude.flatten()))
    return pressure.reshape(altitude.shape)