code: def test_perceiver_self_attention(self):
      sa = SelfAttention(num_channels=10, num_heads=5, dropout=0.2)
      q_tensor = torch.rand(2, 10, 10)
      out = sa(q_tensor)  # torch.Size([2, 10, 10])
      self.assertTrue(out.shape == torch.Size([2, 10, 10]))
  
imports: import unittest
  import torch
  from towhee.models.perceiver.self_attention import SelfAttention
label_desc: Use image node_id 1 for calling the PerceiverSelfAttentionTest obj's underlying member method code with example usage: obj.test_perceiver_self_attention() without return types