use of dictionaries

#Dictionary features #     . dict is unordered 
#     . The key must be unique, so is born to deduplicate

dixt = { ' caicai ' :33, ' wuwu ' :22}

of = { ' xingming ' : ' caicai ' , " age " :33, " opne " :13421731046, " qq " :75738369 }
 #If the key xingming exists, modify it, if it does not exist, create 
of[ " xingming " ] = " Cai Cai " 
of[ " XingM " ] = " Cai Cai " 
# #delete del of
 [ " XingM " ]
of.pop( " xingming " )
 #Randomly delete 
of.popitem()

# Find--If not found, return None, if found, return value 
print (of.get( " opne " ))
 # Find--If found, return True, if not found, return False 
print ( ' opne '  in of)

print(of)

###多层嵌套
catalog = {
    "oumei":{"www01":["01","01"],"www02":"02","www03":"03"},
"rihan":{"www04":"04","www05":"05","www06":"06"},
"dalu":{"www07":"07","www08":"08","www09":"09"}
}
# ##Modify a value 
catalog[ " oumei " ][ " www01 " ][1] = " 08 " 
print (catalog)

# #Update if there is this dictionary, create 
b = { ' dalu ' : { ' www17 ' : ' 17 ' , ' www18 ' : ' 18 ' , ' www19 ' : ' 19 ' }}
catalog.update(b)
print(catalog)

#loop in dictionary 
for i in catalog:
     print (i,catalog[i])

# #The dict will be converted into a list first. When the amount of data is large, do not use 
for k, v in catalog.items():
     print (k,v)