#NEWLINE# def decr( self , key , delta = 1 , version = None ) : #NEWLINE# #INDENT# key = self . make_key ( key , version = version ) #NEWLINE# try : #NEWLINE# #INDENT# val = self . _cache . decr ( key , delta ) #NEWLINE# #UNINDENT# except self . LibraryValueNotFoundException : #NEWLINE# #INDENT# val = None #NEWLINE# #UNINDENT# if ( key is None ) : #NEWLINE# #INDENT# raise ValueError ( ( "Key '%s' not found" % key ) ) #NEWLINE# #UNINDENT# return val