# Dictionary in Python

# Creating a dictionary

dict = {
        'John': 'john.smith@gmail.com',
        'Mary': 'mary.johnson@gmail.com',
        'Richard': 'richard.jackson@gmail.com',
        'Cindy': 'cindy.mcgregor@gmail.com',
        'Jessica': 'jessica.jones@gmail.com'
        }

# Accessing a single element

print("John's address is", dict['John'])

# Deleting a key-value

del dict['Jessica']

# Adding a key-value pair

dict['Mark'] = 'mark.zuckerberg@gmail.com'

# Find the count of dict elements

print('\nThere are {} contacts in the address-book\n'.format(len( dict)))

# Accessing the whole dictionary

for name, address in dict.items():
        print('Contact {} at {}'.format(name, address))

# Checking if a value is the dictionary

if 'Cindy' in dict:
        print("\nCindy's address is", dict['Cindy'])