Add custom update method

[Shyamala7]

(Provide a general summary of your changes in the Title above)

Description

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Motivation and Context

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How Has This Been Tested?

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Checklist:

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• My code follows the code style of this project.
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• I have added tests to cover my changes.
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Thank you!

[mtahirtariq]

TODO: Fix update method to work with queryset instead of a single object.