Create change_brightness.py
diff --git a/digital_image_processing/change_brightness.py b/digital_image_processing/change_brightness.py
new file mode 100644
index 000000000000..97493f1a399e
--- /dev/null
+++ b/digital_image_processing/change_brightness.py
@@ -0,0 +1,26 @@
+from PIL import Image
+
+
+def change_brightness(img: Image, level: float) -> Image:
+    """
+    Change the brightness of a PIL Image to a given level.
+    """
+
+    def brightness(c: int) -> float:
+        """
+        Fundamental Transformation/Operation that'll be performed on
+        every bit.
+        """
+        return 128 + level + (c - 128)
+
+    if not -255.0 <= level <= 255.0:
+        raise ValueError("level must be between -255.0 (black) and 255.0 (white)")
+    return img.point(brightness)
+
+
+if __name__ == "__main__":
+    # Load image
+    with Image.open("image_data/lena.jpg") as img:
+        # Change brightness to 100
+        brigt_img = change_brightness(img, 100)
+        brigt_img.save("image_data/lena_brightness.png", format="png")

### **Describe your change:**



* [x] Add an algorithm?
* [ ] Fix a bug or typo in an existing algorithm?
* [ ] Documentation change?

### **Checklist:**
* [x] I have read [CONTRIBUTING.md](https://github.com/TheAlgorithms/Python/blob/master/CONTRIBUTING.md).
* [x] This pull request is all my own work -- I have not plagiarized.
* [x] I know that pull requests will not be merged if they fail the automated tests.
* [x] This PR only changes one algorithm file.  To ease review, please open separate PRs for separate algorithms.
* [x] All new Python files are placed inside an existing directory.
* [x] All filenames are in all lowercase characters with no spaces or dashes.
* [x] All functions and variable names follow Python naming conventions.
* [x] All function parameters and return values are annotated with Python [type hints](https://docs.python.org/3/library/typing.html).
* [x] All functions have [doctests](https://docs.python.org/3/library/doctest.html) that pass the automated testing.
* [ ] All new algorithms have a URL in its comments that points to Wikipedia or other similar explanation.
* [ ] If this pull request resolves one or more open issues then the commit message contains `Fixes: #{$ISSUE_NO}`.
