def get_helmholtz_volume(self):
    warnings.warn('QHA.get_helmholtz_volume() is deprecated.Use helmholtz_volume attribute.', DeprecationWarning)
    return self.helmholtz_volume
def get_helmholtz_volume(self):
    warnings.warn('QHA.get_helmholtz_volume() is deprecated.Use helmholtz_volume attribute.', DeprecationWarning)
    return self.helmholtz_volume