basic_dictionary.py

# Defining a dictionary
>>> tel = {'jack': 4098, 'sape': 4139}

# If dict keys are only string, we can define as below
>>> dict(sape=4139, guido=4127, jack=4098)
{'sape': 4139, 'jack': 4098, 'guido': 4127}

# Appending a new key value pair to the `tel` dict
>>> tel['guido'] = 4127

# Display items in dictionary 
>>> tel
{'sape': 4139, 'guido': 4127, 'jack': 4098}

# Delete a item from `tel` dict 
>>> del tel['sape']

# Represent all the keys of the `tel` in a list
>>> list(tel.keys())
['irv', 'guido', 'jack']

# sort the keys 
>>> sorted(tel.keys())
['guido', 'irv', 'jack']

# Check whether a key exists in the `tel` dict 
>>> 'guido' in tel
True

>>> 'jack' not in tel
False