docs: add new chapter on File Input and Output (I/O) in Python

Author: codewithdhruba01

docs/python/python-io.md

@@ -0,0 +1,152 @@
+---
+id: python-io
+title: File Input and Output (I/O) in Python
+description: Learn how to read from and write to files using Python's built-in I/O functions.
+sidebar_label: File I/O in Python
+sidebar_position: 13
+tags:
+  [
+    Python,
+    List in Python,
+    Introduction of python,
+    Python Syntax,
+    Variables,
+    Operators,
+    Type Casting,
+    String,
+    Tuple in Python
+    Array in Python
+    Functions in Python
+    Recursion in Python
+    Opps in Python
+  ]
+---
+
+# File Input and Output (I/O) in Python
+
+In Python, file I/O is used to read from or write to files. This is an essential part of any programming language when it comes to data processing, logging, or configuration.
+
+
+## Opening Files
+
+To work with files in Python, you use the built-in `open()` function.
+
+```python
+file = open("example.txt", "r")  # Open for reading
+````
+
+### Modes:
+
+| Mode  | Description                                          |
+| ----- | ---------------------------------------------------- |
+| `'r'` | Read (default). Fails if the file doesn’t exist.     |
+| `'w'` | Write. Creates a new file or truncates existing one. |
+| `'a'` | Append. Adds content to the end of the file.         |
+| `'b'` | Binary mode. Used with `'rb'`, `'wb'`, etc.          |
+| `'x'` | Create. Fails if the file already exists.            |
+
+
+## Reading from a File
+
+### `read()` – Reads entire content
+
+````python
+with open("example.txt", "r") as file:
+    content = file.read()
+    print(content)
+````
+
+### `readline()` – Reads one line at a time
+
+````python
+with open("example.txt", "r") as file:
+    line = file.readline()
+    print(line)
+````
+
+### `readlines()` – Reads all lines into a list
+
+````python
+with open("example.txt", "r") as file:
+    lines = file.readlines()
+    print(lines)
+````
+
+## Writing to a File
+
+### `write()` – Write string to file
+
+````python
+with open("output.txt", "w") as file:
+    file.write("Hello, world!")
+````
+
+### `writelines()` – Write list of strings
+
+````python
+lines = ["Line 1\n", "Line 2\n"]
+with open("output.txt", "w") as file:
+    file.writelines(lines)
+````
+
+
+## Using `with` Statement (Best Practice)
+
+The `with` block ensures the file is automatically closed after use:
+
+````python
+with open("data.txt", "r") as file:
+    data = file.read()
+````
+
+This is the **recommended way** to handle files in Python.
+
+
+## Error Handling in File I/O
+
+Always handle file operations with care to avoid exceptions:
+
+````python
+try:
+    with open("config.txt", "r") as file:
+        config = file.read()
+except FileNotFoundError:
+    print("File not found.")
+except IOError:
+    print("Error while handling the file.")
+````
+
+
+## File Paths
+
+You can also handle file paths using the `os` or `pathlib` module:
+
+````python
+from pathlib import Path
+
+file_path = Path("docs") / "myfile.txt"
+with open(file_path, "r") as file:
+    print(file.read())
+````
+
+
+## Example: Reading & Writing
+
+````python
+# Write to a file
+with open("sample.txt", "w") as file:
+    file.write("This is a test.")
+
+# Read the file
+with open("sample.txt", "r") as file:
+    print(file.read())
+````
+
+
+##  Summary
+
+* Use `open()` to access files.
+* Use `read()`, `readline()`, or `readlines()` to read.
+* Use `write()` or `writelines()` to write.
+* Always use `with` to handle files safely.
+* Handle exceptions for robustness.

docs/python/setup-environment.md

@@ -2,7 +2,7 @@
 id: setup-environment
 title: Setting up your development environment
 sidebar_label: Setting up environment
-sidebar_position: 13
+sidebar_position: 14
 tags:
   [
     html,