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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 quat2Roll (self, qw, qx, qy, qz):
        '''
        Translates from Quaternion to Roll. 

        @param qw,qx,qy,qz: Quaternion values

        @type qw,qx,qy,qz: float

        @return Roll value translated from Quaternion

        '''
        rotateXa0=2.0*(qy*qz + qw*qx)
        rotateXa1=qw*qw - qx*qx - qy*qy + qz*qz
        rotateX=0.0

        if(rotateXa0 != 0.0 and rotateXa1 != 0.0):
            rotateX=atan2(rotateXa0, rotateXa1)
        return rotateX