students={100:{"roll":10,"name":"sree","course":"bca"},
         110:{"roll":11,"name":"abc","course":"mca"}}
#print student name
#print(students["name"])
#print students course
##print(students["course"])
#iterate
#for keys in students:
 #   print(keys,students[keys])
#searching specific key
#print("roll" in students)
#add missing value
#if("total" not in students):
 #   students["total"]=150
print(students[100]["name"])
#add total to 50
#students["total"]+=50
#print(students)