Incubator-superset: Error while importing dashboard with druid datasource

[Ujwala92]

A clear and concise description of what the bug is.

Expected results
Successfully Import dashboard with druid datasource

Actual results

AttributeError: type object 'dict' has no attribute 'import_obj'

If applicable, add screenshots to help explain your problem.

How to reproduce the bug

1. Go to 'Manage'
2. Click on 'Import Dashboard'
3. Choose file
   4.Click on Upload Button
4. See error

Environment

(please complete the following information):

• superset version: superset 0.28.1
• python version: python 3.6

Checklist

Make sure these boxes are checked before submitting your issue - thank you!

• [ ] I have checked the superset logs for python stacktraces and included it here as text if there are any.
• [ ] I have reproduced the issue with at least the latest released version of superset.
• [ ] I have checked the issue tracker for the same issue and I haven't found one similar.

Additional context

Import dashboard with druid datasource but there is error of type object 'dict' has no attribute 'import_obj'.Please help me why this error occur and what settings need to do for solve this problem. Thanks in advance.

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[syazwan0913]

Same issue here

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. For admin, please label this issue .pinned to prevent stale bot from closing the issue.

[tuhangdi]

same problem

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. For admin, please label this issue .pinned to prevent stale bot from closing the issue.