#coding=utf-8

#python里面的字典，用｛｝来表示

book={'title':'python web development','year':2008}

print book

print 'year' in book

print 'pub'  in book

print book.get('pub','N/A')

book['pub']='Addison Wesley'

print book.get('pub','N/A')

for key in book:

	print key,':',book[key]