Function projection_parameter_group 

pub fn projection_parameter_group<T, M>(
    logical_name: impl Into<String>,
    role: ParameterRole,
    module: &M,
    placement: ProjectionSharding,
) -> Result<ParameterGroupSpec, ParallelPlanError>
where
    T: Tensor,
    M: Parameterized<T>,

Describes one affine projection and all encoding companions.