Code Explanation:
🔹 1. Importing the ast Module
import ast
✅ Explanation
ast stands for Abstract Syntax Tree.
It is a built-in Python module used to work with Python source code.
ast.literal_eval() safely converts a string containing Python literals into actual Python objects.
Unlike eval(), it cannot execute arbitrary code, making it much safer.
ast Module
│
▼
literal_eval()
↓
Safely Convert String
↓
Python Object
Nothing executes yet.
🔹 2. Creating a String
text = "{'x':[1,2,3]}"
✅ Explanation
A string is created.
Although it looks like a dictionary, it is still just plain text.
Current Memory
text
↓
"{'x':[1,2,3]}"
Type
↓
str
Visual Representation
+------------------+
| "{'x':[1,2,3]}" |
+------------------+
It is not a dictionary yet.
🔹 3. Converting the String
obj = ast.literal_eval(text)
✅ Explanation
literal_eval() reads the string and converts it into a real Python object.
String
"{'x':[1,2,3]}"
becomes
{'x': [1, 2, 3]}
Current Memory
obj
↓
Dictionary
{
'x' : [1,2,3]
}
Visual Representation
obj
│
▼
Dictionary
┌──────────────┐
│ x ─────────┐ │
└────────────┼─┘
▼
+---+---+---+
| 1 | 2 | 3 |
+---+---+---+
Now obj is a real Python dictionary.
🔹 4. Accessing the Dictionary Value
obj["x"]
✅ Explanation
Python looks for the key "x".
Current Memory
Dictionary
'x'
↓
[1,2,3]
Returned value
[1, 2, 3]
🔹 5. Accessing the Last Element
obj["x"][-1]
✅ Explanation
[-1] means last element of the list.
Visual Representation
List
+----+----+----+
| 1 | 2 | 3 |
+----+----+----+
0 1 2
Negative Index
-3 -2 -1
▲
│
3
Python returns
3
🔹 6. Printing the Result
print(obj["x"][-1])
✅ Explanation
Python prints the last element of the list.
Output
3
🎯 Final Output
3
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