Define a class that meets the following specifications. Class name: WaterBody Class constructor parameter: 1. int/float Assign this number to the instance attribute volume The class has class attributes RHO = 997 and G = 9.81. Define a class method for the WaterBody class that meets the following specifications. Method name : get_hydrostatic_pressure Method parameter: 1. float Method type: Class method Return value: 1. float Using the input float, the depth. calculate and return the hydrostatic pressure. Hydrostatic pressure a given depth = RHO*G*depth If the depth is less than 0, the static method should raise an InvalidDepthError. Define a instance method for the WaterBody class that meets the following specifications. Method name: get_water_mass Method type: Instance method Return value: 1. Float This method should return the mass of the waterbody given that mass = RHO* volume

Here is the code for the WaterBody class that meets the given specifications:

class WaterBody:
    RHO = 997
    G = 9.81
    
    def __init__(self, volume):
        self.volume = volume
        
    @classmethod
    def get_hydrostatic_pressure(cls, depth):
        if depth < 0:
            raise InvalidDepthError("Depth cannot be less than 0")
        else:
            return cls.RHO * cls.G * depth
    
    def get_water_mass(self):
        return self.RHO * self.volume

In the above code, we have defined a class named WaterBody with a class attribute RHO and G. We have also defined a constructor that takes an int/float parameter and assigns it to the instance attribute volume.

We have then defined a class method get_hydrostatic_pressure that takes a float parameter depth and calculates the hydrostatic pressure using the formula RHO * G * depth. If the depth is less than 0, it raises an InvalidDepthError.

Lastly, we have defined an instance method get_water_mass that returns the mass of the waterbody using the formula RHO * volume.

Note: The InvalidDepthError is not defined in the code snippet and needs to be defined separately.