Google App Engine : Select from the artifact list by supplying the number: What does the number mean?

What i am doing

1. I am trying to use the google app engine for the first time


2. I have installed JAVA & Maven as specified by docs

[LINK I AM REFERING: https://cloud.google.com/appengine/docs/java/gettingstarted/creating ][1]

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I am trying to run:

mvn archetype:generate -Dappengine-version=1.9.17 -Dapplication-id=XXXXXX -Dfilter=com.google.appengine.archetypes:

Application-id: I got from the google console

Doc says :: Select from the artifact list by supplying the number corresponding to

com.google.appengine.archetypes:appengine-skeleton-archetype.

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Questions

1. What does it mean by "number"?


2. Where can we get that number ?


3. Confused on this part !

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