items(): if value == target_value: return key return None my_dict = {'a': 1, 'b': 2, 'c': 3} result = find_key_by_value(my_dict, 2) Output: b In this example, we define a function called find_key_by_value that takes a dictionary and a target value as arguments. ...
In the above code, we first initialize a dictionary and then add a newkey-valuepair to the dictionary usingdictionary[key]. If thekeydoes not exist, then this newkey-valuepair is added to the dictionary. If thekeyalready exists, then the value of the existingkeyis updated to the newvalu...
则获取对应的值ifkey_inputinmy_dict:value=my_dict[key_input]print(f"The value of key '{key_input}' is '{value}'")else:print("Key not found in the dictionary")
下面的示例代码演示了如何使用这个函数: my_dict={'a':1,'b':2,'c':3,'d':1}value_to_find=2key=find_key_by_value(my_dict,value_to_find)ifkeyisnotNone:print(f"The key corresponding to value{value_to_find}is{key}.")else:print(f"The value{value_to_find}does not exist in the ...
In Python, dictionary data types are used to store data collection in key-value syntax. Every key in the dictionary has a unique value that can be accessed in a program using the specified key name. Python offers various methods to apply some operations on the keys of a dictionary. ...
def find_keys_by_value(dictionary, search_value): return [key for key, value in dictionary.items() if value == search_value] 二、通过循环遍历字典查找键 如果对于列表推导式不够熟悉或者需要在找到键的同时完成其他操作,可以采用传统的循环遍历方法。循环遍历允许在整个字典上进行迭代,并在找到目标值时采...
In simple terms, a Python dictionary can store pairs of keys and values. Each key is linked to a specific value. Once stored in a dictionary, you can later obtain the value using just the key. For example, consider the Phone lookup, where it is very easy and fast to find the phone ...
} # 新dictionary：value: keyinverted_dict= {value: key for key, value in d.items()} find_...
If you wanted to sort a dictionary in-place, then you’d have to use the del keyword to delete an item from the dictionary and then add it again. Deleting and then adding again effectively moves the key-value pair to the end. The OrderedDict class has a specific method to move an ite...
Keys of a dictionary must be immutable Immutable objects can't be changed once created. Some immutable objects in Python are integer, tuple and string. # valid dictionary# integer as a keymy_dict = {1:"one",2:"two",3:"three"}# valid dictionary# tuple as a keymy_dict = {(1,2):...