System information (version)

• OpenCV => :4.4.0.46
• Operating System / Platform => :ubuntu 18.04
• onnx => :1.8.0

Detailed description

when i wanted onnx to cv2, and the problem was :
error: (-2:Unspecified error) Can't create layer "195" of type "Einsum" in function 'getLayerInstance'

Steps to reproduce

feature_shape = feature_maps.size() ## 12,768,26,26
attention_shape = attention_maps.size() ## 12,32,26,26
phi_I = torch.einsum('imjk,injk->imn', (attention_maps, feature_maps)) 12,32,768

pytorch -- > onnx -- [no problem]
but
onnx --> opencv -- [worry]

Issue submission checklist

• I report the issue, it's not a question

[** ] I checked the problem with documentation, FAQ, open issues,
answers.opencv.org, Stack Overflow, etc and have not found solution

[ **] I updated to latest OpenCV version and the issue is still there

• There is reproducer code and related data files: videos, images, onnx, etc