fix similar code issue in mail.js helper as per #458

[adiman9]

I removed the duplicate code and refactored into a more general loop to reuse the code.

[SendGridDX]

All committers have signed the CLA.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@79d5ea7). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master     #488   +/-   ##
=========================================
  Coverage          ?   82.87%           
=========================================
  Files             ?       30           
  Lines             ?     1016           
  Branches          ?      157           
=========================================
  Hits              ?      842           
  Misses            ?       84           
  Partials          ?       90

Impacted Files	Coverage Δ
sendgrid/helpers/mail/mail.py	97.38% <100%> (ø)

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[thinkingserious]

@adiman9

We have not been able to merge your Pull Request, but because you are awesome - we wanted to make sure you could still get a SendGrid Hacktoberfest shirt.

Please go fill out our swag form before Nov 5th and we will send the shirt! (We know that you might have tried this before and it didn’t work, sorry about that!)

You have till Nov 5th to fill out this form in order to get the Hacktoberfest shirt!

Thank you for contributing during Hacktoberfest! We hope to see you in the repos soon! Just so you know, we always give away a SendGrid shirt for your first ever non-Hacktoberfest PR that gets merged.

[thinkingserious]

Hi @adiman9,

I'm looking to merge this within the coming weeks. Now that we've launched our PHP SDK v7 I'm turning my focus to this SDK. Could you please take a moment to resolve the merge conflicts.

Thanks!

With Best Regards,

Elmer

[thinkingserious]

Thanks again for helping improve this SDK!

We have started to execute on PR #347 (Python Mail Helper Refactor) and have integrated your work into this branch. Please follow along at PR #347 to follow our progress.

With Best Regards,

Elmer