Hello,

After adding adding a parametrization module with:

```
torch.nn.utils.parametrize.register_parametrization(
self.conv, "weight", _SumOne()
)
```

, when does the `forward()`

function of `_SumOne()`

get called? The `forward`

function makes is so that the sum of the weights is 1:

```
def forward(self, weight: torch.Tensor) -> torch.Tensor:
return torch.divide(weight, weight.sum())
```

Is it called when the weights are accessed (in the forward and backward passes) or only when the weights are modified (in the backward pass)?

Note: `self.conv`

is a `torch.nn.Conv2d`

Thanks.