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+File handling in Python is about managing files on your system to read or write data. Python provides built-in functions to open, read, write, and close files, making it efficient for data storage and retrieval.
+
+### Opening a File
+
+To start working with a file, it must be opened using the `open()` function, which returns a file object. You can specify the file path and the mode in which you want to open the file:
+
+- `"r"`: Read mode (default) – Opens a file for reading; error if the file doesn’t exist.
+- `"w"`: Write mode – Opens a file for writing; creates a new file if it doesn’t exist or truncates the existing file.
+- `"a"`: Append mode – Opens a file for appending; creates a new file if it doesn’t exist.
+- `"r+"`: Read and write mode – Opens a file for both reading and writing.
+
+Example:
+```python
+file = open("example.txt", "r")  # Opens file in read mode
+```
+
+### Reading from a File
+
+Python provides multiple methods for reading files, depending on how you want to access the data:
+
+1. **`read()`**: Reads the entire file.
+2. **`readline()`**: Reads a single line from the file.
+3. **`readlines()`**: Reads all lines as a list of strings.
+
+#### Example of reading a file:
+```python
+# Reading the entire file content
+file = open("example.txt", "r")
+content = file.read()
+print(content)
+file.close()
+
+# Reading line by line
+file = open("example.txt", "r")
+for line in file:
+    print(line.strip())  # Remove newline character
+file.close()
+```
+
+### Writing to a File
+
+When writing to a file, you can use:
+- **`write()`**: Writes a string to the file.
+- **`writelines()`**: Writes a list of strings to the file.
+
+#### Example of writing to a file:
+```python
+# Writing a single line to a file
+file = open("example.txt", "w")
+file.write("Hello, world!\n")
+file.close()
+
+# Writing multiple lines
+lines = ["This is line 1.\n", "This is line 2.\n"]
+file = open("example.txt", "w")
+file.writelines(lines)
+file.close()
+```
+
+### Appending to a File
+
+Using append mode (`"a"`) allows you to add content without overwriting existing data.
+
+#### Example of appending to a file:
+```python
+file = open("example.txt", "a")
+file.write("This is a new line added to the file.\n")
+file.close()
+```
+
+### Using `with` Statement for File Handling
+
+The `with` statement is the preferred way to handle files as it ensures the file is properly closed after its suite finishes, even if an exception is raised.
+
+```python
+# Reading with 'with' statement
+with open("example.txt", "r") as file:
+    content = file.read()
+    print(content)
+
+# Writing with 'with' statement
+with open("example.txt", "w") as file:
+    file.write("Using 'with' to handle files in Python.\n")
+```
+
+### Example: Reading and Writing Data to a File
+
+Here’s a practical example where we read a list of names from a file, process them, and write them to another file:
+
+```python
+# Read names from 'input.txt' and write each name in uppercase to 'output.txt'
+with open("input.txt", "r") as infile, open("output.txt", "w") as outfile:
+    for line in infile:
+        outfile.write(line.strip().upper() + "\n")
+```
+
+In this example:
+1. The `input.txt` file is read line-by-line.
+2. Each line is converted to uppercase and written to `output.txt`.
+
+File handling is powerful and flexible, letting you easily manage persistent data in Python scripts.