#NEWLINE# def flatten( self ) : #NEWLINE# #INDENT# '\n        Recursively yield this expression and all subexpressions, in\n        depth-first order.\n        ' #NEWLINE# ( yield inner_expr ) #NEWLINE# for expr in self . get_source_expressions ( ) : #NEWLINE# #INDENT# if expr : #NEWLINE# #INDENT# for inner_expr in expr . flatten ( ) : #NEWLINE# #INDENT# ( yield inner_expr )