#NEWLINE# @ classmethod #NEWLINE# def setup_mappers( cls ) : #NEWLINE# #INDENT# ( Child , Parent , parent , child ) = ( cls . classes . Child , cls . classes . Parent , cls . tables . parent , cls . tables . child ) #NEWLINE# mapper ( Parent , parent , properties = { #NEWLINE# #INDENT# 'children' : relationship ( Child , backref = 'parent' ) , #NEWLINE# #UNINDENT# } ) #NEWLINE# mapper ( Child , Parent )