How to read Dictionary from File in Python?

A Dictionary in Python is collection of key-value pairs, where key is always unique and oftenly we need to store a dictionary and read it back again.

We can read a dictionary from a file in 3 ways:

1. Using the json.loads() method : Converts the string of valid dictionary into json form.
2. Using the ast.literal_eval() method : Function safer than the eval function and can be used for interconversion of all data types other than dictionary as well.
3. Using the pickle.loads() method : We can also use Pickle module if the file is serialized into a character stream.

Input File:

Method 1 : Using json.loads() :

Output :

Data type before reconstruction :  <class 'str'>
Data type after reconstruction :  <class 'dict'>
{'Name': 'John', 'Age': 21, 'Id': 28}

Method 2 : Using ast.literal_eval() :

Output :

Data type before reconstruction :  <class 'str'>
Data type after reconstruction :  <class 'dict'>
{'Name': 'John', 'Age': 21, 'Id': 28}

Method 3 : We can use the Pickle module for the same purpose, but this method will only work if the file is serialized into a character stream and not in text format. To know more about Pickling in Python click here

Output :

Data type before reconstruction :  <class 'bytes'>
Data type after reconstruction :  <class 'dict'>
{'Name': 'John', 'Age': 21, 'Id': 28}