Compare with javascript object
In Python, dictionaries are data structures that store key-value pairs. Each key maps to a unique value within the dictionary, and you can use the keys to look up the corresponding values. For example:
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| person = {'name': 'John', 'age': 32, 'city': 'New York'}
print(person['name']) # Output: John
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In JavaScript, objects serve a similar purpose as dictionaries in Python. They also store key-value pairs, and you can use the keys to look up the corresponding values. For example:
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| const person = {name: 'John', age: 32, city: 'New York'};
console.log(person.name); // Output: John
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However, their ways to refer to items different as shown above.
Similarly, lists in Python and arrays in JavaScript are similar.
Dictionary
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| acronyms = {
'LOL': 'laugh out loud',
'IDK': "I dont' know", # note the different quotes to avoid problem
'TBH': 'to be honest'
}
print(acronyms)
print(acronyms['IDK']) # Refer to one item
acronyms['TBH'] = "honestly" #Update an item
print(acronyms['TBH'])
# print(acronyms['BTW']) KeyError: 'BTW' when there is no such a key
print(acronyms.get('BTW')) # Get None if the key doesn't exist
acronyms['BTW'] = "by the way" # Add an item if it's not exist
print(acronyms['BTW'])
del acronyms['LOL'] # Delete
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None Type
None is a type that represents the absence of a value, it also evaluates to False
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| if acronyms.get('BTW'): # Use what None type evaluates to for condition
print(acronyms.get('BTW'))
else:
print("key BTW is not there")
if acronyms.get('LOL') != None: # Use None type itself to compare
print(acronyms.get('LOL'))
else:
print("key LOL is not there")
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