In Python, you can iterate over a dictionary using various techniques. Here's a detailed explanation of a few commonly used methods:
Iterating over keys:
By default, when you iterate over a dictionary using a loop, it iterates over the keys of the dictionary.
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my_dict = {'a': 1, 'b': 2, 'c': 3}
for key in my_dict:
print(key)
In this example, the loop iterates over the keys of themy_dict dictionary, and each key is printed.
Iterating over values:
To iterate over the values of a dictionary, you can use thevalues() method.
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my_dict = {'a': 1, 'b': 2, 'c': 3}
for value in my_dict.values():
print(value)
In this example, the loop uses thevalues() method to iterate over the values of themy_dict dictionary, and each value is printed.
Iterating over key-value pairs:
To iterate over both the keys and values of a dictionary simultaneously, you can use theitems() method.
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my_dict = {'a': 1, 'b': 2, 'c': 3}
for key, value in my_dict.items():
print(key, value)
In this example, the loop uses theitems() method to iterate over the key-value pairs of themy_dict dictionary. The loop assigns each key to the variablekey and each value to the variablevalue, and they are printed together.
Using list comprehension:
You can also use list comprehension to create a new list based on the dictionary's keys, values, or items.
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my_dict = {'a': 1, 'b': 2, 'c': 3}
keys = [key for key in my_dict]
values = [value for value in my_dict.values()]
items = [(key, value) for key, value in my_dict.items()]
print(keys)
print(values)
print(items)
In this example, list comprehensions are used to create new lists based on the keys, values, or items of themy_dict dictionary. The resulting lists are then printed.
These are a few commonly used methods to iterate over a dictionary in Python. Choose the method that best suits your needs based on whether you want to iterate over the keys, values, or key-value pairs of the dictionary.
