Make a function which will calculate the pressure of a gas using Van der Waals Equation:

The Van der Waals function will have arguments:

temperature (T) in Kelvin,
molar volume (Vₘ) in L/mole,
critical temperature (T) in Kelvin and
critical pressure (P) in atm.
(T and P are characteristics of the substance.)

Within the function also define the gas constant R= 0.08206 L·atm/mole·K.

The Van der Waals equation to calculate the pressure, P is: