Contents
Python Dictionary – Get Value for a Key
Python dict.get() method returns the value corresponding to the specified key.
This tutorial introduces you to get() method of Dictionary class in Python, and its usage, with the help of example programs.
Syntax
The syntax of dictionary get() method is
dictionary.get(key, value)
where
Parameter | Description |
---|---|
key | [mandatory] The key for which value has to be fetched from the dictionary. |
value | [optional] If specified key does not exist, get() returns this value. |
Return Value
- dict.get() returns the value corresponding to the specified key, if present.
- If the key is not present, and value (second argument) is given, then get() returns this value.
- If the key is not present, and value (second argument) is not given, then get() returns None.
Examples
1. A simple example for dictionary get()
In this example, we will create a dictionary with some key:value pairs, and use get() method to access values corresponding to the specific keys we provide as arguments.
Python Program
myDict = {
'foo':12,
'bar':14
}
print(myDict.get('bar'))
Run Output
14
‘bar’ key is present in the dictionary. Therefore, get() method returned the value corresponding to that key.
2. Dictionary get() – Key not present
In this example, we will create a dictionary with some key:value pairs, and use get() method to access value corresponding to a specific key that is not present in the dictionary.
Python Program
myDict = {
'foo':12,
'bar':14
}
#key not present in dictionary
print(myDict.get('moo'))
Run Output
None
The key ‘moo’ is not present in the dictionary. Also, we have not given any second argument to get() method for default value. In these kind of scenarios, as we already see in Return Value section, Dictionary.get() method returns value None
of type NoneType
.
3. Dictionary get() – Default value
You can also tell get() method to return a default value instead of None, if key-value pair is not present for the key specified. Provide the default value as second argument to get() method.
Python Program
myDict = {
'foo':12,
'bar':14
}
print(myDict.get('moo', 10))
Run Output
10
dict.get() vs Accessing dict using index
Most of the times, you would see or use indexing style of accessing values of a dictionary with key as index. A sample code snippet is
value1 = myDictionary[key1]
There is a downside of using this style. Which is, when there is no key:value pair for the key we have mentioned, you would get KeyError.
Following is a example demonstrating how using square brackets to get a value corresponding to given key in dictionary ends up with KeyValue error.
Python Program
myDict = {
'foo':12,
'bar':14
}
print(myDict['moo'])
Run Output
Traceback (most recent call last):
File "example.py", line 6, in <module>
print(myDict['moo'])
KeyError: 'moo'
So, you may have to explicitly check if the key is present, and then access the dictionary using key as index.
Summary
In this tutorial of Python Examples, we learned how to use Dictionary get() method to access values, with help of well detailed Python programs.