#NEWLINE# def merge_aes( layer1 , layer2 ) : #NEWLINE# #INDENT# 'Merges the aesthetics dictionaries for the two layers.\n    Look up sequence_layers function. Which layer is first and which\n    one is second is important.\n\n    Parameters:\n    -----------\n    layer1: Layer object\n    layer2: Layer object\n    ' #NEWLINE# for key in layer2 . aes . keys ( ) : #NEWLINE# #INDENT# if ( layer2 . aes [ key ] is None ) : #NEWLINE# #INDENT# layer2 . aes [ key ] = layer1 . aes [ key ]