Dictionaries:

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stu = {'name':'sundeep','age':25,'courses':['ssis','ssrs','ssas'],1:'value'}

print(stu)

print(stu['name'])

print(stu['courses'])

print(stu[1])

#print(stu['key']) # throws error if we try to access key which does not exist

print(stu.get('name'))

print(stu.get('key')) # if we use get method to access which does not exist then it will not

# throw any error

if stu.get('key','not found') == 'not found': # we can pass some default value when key does not exist.

print('key does not exist')

stu['phone'] = '3333333' # this will add new key to the dict

print(stu['phone'])

stu['phone'] = '999999' # this will update the key if it already exists

print(stu['phone'])

key = 'key'

name = 'newkey'

stu.update({key:name,'age':35}) # we can add or update multiple key values using update method.

print(stu)

del stu['key']

print(stu)

age = stu.pop('age')

print(stu,age)

print(len(stu)) # returns how many key/value pairs are there

print(stu.keys()) # retuns only keys

print(stu.values()) # returns only values

print(stu.items()) # returns both keys & values

for key,val in stu.items():

print(key,val)