Was unable to import app Error: Install 'email_validator'

[kitson618]

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Environment

Python 3.6.10

Flask-Appbuilder version:
2.3.2

Describe the expected results

Tell us what should happen.

Able to create an admin user by running "fabmanager create-admin"

Describe the actual results

Tell us what happens instead.

An Error message shows: 
Was unable to import app Error: Install 'email_validator' for email validation support.

Probably setup.sh missing the plugin "email_validator"

Steps to reproduce

1. pip install flask-appbuilder
2. fabmanager create-app
3. fabmanager create-admin

An error will be hit ->
Was unable to import app Error: Install 'email_validator' for email validation support.

[dpgaspar]

I'm able to reproduce, this is related with this issue also: #1356

Do the following:

pip install wtforms==2.2.1

[dpgaspar]

New FAB 2.3.3 fixes this problem