src/transformers/models/mvp/modeling_mvp.py/MvpPrompt/forward
class MvpPrompt:    def forward(self, prompt_ids: torch.Tensor) -> Tuple[torch.Tensor]:
        prompt = self.prompt_trans(self.prompt_embedding(prompt_ids))
        prompt = prompt.view(self.prompt_length, self.num_layers * 2, self.num_heads, self.head_dim)
        prompt = self.dropout(prompt)
        prompt = prompt.permute([1, 2, 0, 3]).split(2)
        return prompt