Update factories.rst

your factory method should be static to work!
Update factories.rst
Update factories.rst
minor #3770 Update factories.rst (AlaaAttya)

This PR was submitted for the 2.4 branch but it was merged into the 2.3 branch instead (closes #3770).

Discussion
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Update factories.rst

your factory method should be static to work!

Commits
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97ed5ce Update factories.rst
aefc36c Update factories.rst
a9cfdb2 Update factories.rst