type conversion between alias types

alias type = DType.float32

struct Matrix[rows: Int, cols: Int]:
    var data: DTypePointer[type]

    @staticmethod
    fn rand() -> Self:
        var data = DTypePointer[type].alloc(rows * cols)
        rand(data, rows * cols)
        return Self(data)

struct Logits[rows: Int]:
    alias LogitsM = Matrix[rows, 1]
    var logits: Self.LogitsM
    fn __init__(inout self):
        self.logits.__init__()
    @staticmethod
    fn rand() -> Self:
        return Self.LogitsM.rand()

error: Expression [20]:9:33: cannot implicitly convert 'Matrix[rows, 1]' value to 'Logits[rows]' in return value
        return Self.LogitsM.rand()
               ~~~~~~~~~~~~~~~~~^~
expression failed to parse (no further compiler diagnostics)