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Test Plan: manual

Reviewers: prha, alangenfeld

Reviewed By: alangenfeld

Subscribers: alangenfeld

Differential Revision: https://dagster.phacility.com/D1076

README.md

@@ -37,10 +37,9 @@ Next, jump right into our [tutorial](https://dagster.readthedocs.io/en/stable/se
 
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-<a href="https://tinyurl.com/dagsterslack"><img src="https://user-images.githubusercontent.com/609349/63558739-f60a7e00-c502-11e9-8434-c8a95b03ce62.png" width=160px; /></a>
+<a href="https://join.slack.com/t/dagster/shared_invite/enQtNjEyNjkzNTA2OTkzLTI0MzdlNjU0ODVhZjQyOTMyMGM1ZDUwZDQ1YjJmYjI3YzExZGViMDI1ZDlkNTY5OThmYWVlOWM1MWVjN2I3NjU"><img src="https://user-images.githubusercontent.com/609349/63558739-f60a7e00-c502-11e9-8434-c8a95b03ce62.png" width=160px; /></a>
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 ### Contributing
 
 For details on contributing or running the project for development, check out our [contributing guide](https://dagster.readthedocs.io/en/stable/sections/community/contributing.html).