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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def init_common(app):
 """Post initialization."""

    if app.config['USERPROFILES_EXTEND_SECURITY_FORMS']:
        security_ext = app.extensions['security']
        security_ext.confirm_register_form = confirm_register_form_factory(
            security_ext.confirm_register_form)
        security_ext.register_form = register_form_factory(
            security_ext.register_form)