A tree is a hierarchical data structure used to represent relationships like file systems, organization charts or DOM elements. Python doesn’t have a built-in tree data type but you can easily implement one using classes.
Here are two easy ways to implement trees in Python:
Method 1: Using Simple Class-Based Tree
A basic approach using custom classes to define nodes and children.
Step 1: Define a Node Class
A reusable structure for each node in the tree, including data and child references.
class TreeNode: def __init__(self, data):
self.data = data
self.children = []
def add_child(self, node):
self.children.append(node)
def print_tree(self, level=0):
print(' ' * level + str(self.data))
for child in self.children:
child.print_tree(level + 1)
Step 2: Create the Tree Structure
Builds the tree by connecting parent and child nodes by using the
add_child() method.
# Create root and child nodesroot = TreeNode("Electronics")
laptop = TreeNode("Laptop")
phone = TreeNode("Phone")
root.add_child(laptop)
root.add_child(phone)
laptop.add_child(TreeNode("MacBook"))
laptop.add_child(TreeNode("ThinkPad"))
phone.add_child(TreeNode("iPhone"))
phone.add_child(TreeNode("Samsung"))
# Print the tree
root.print_tree()
Output:
Electronics Laptop
MacBook
ThinkPad
Phone
iPhone
Samsung
This is good for general purpose tree structures in a readable and recursive format.
Also Read: Python Developer Hourly Rate in 2025
Method 2: Using Dictionaries for Lightweight Trees
Use nested dictionaries for simple key-value based trees.
tree = { "Electronics": {
"Laptop": {
"MacBook": {},
"ThinkPad": {}
},
"Phone": {
"iPhone": {},
"Samsung": {}
}
}
}
This is useful for static trees, JSON serialization or quick lookups.
Tip
- Use classes for dynamic, object oriented tree manipulation.
- Use dictionaries when you need quick and lightweight structures—especially for config-like or serialized trees.
- Consider third party libraries like anytree if you need advanced features like tree traversal or exporting.
