diff --git a/brain-jogging.py b/brain-jogging.py
index 576e5e1..4204bfc 100644
--- a/brain-jogging.py
+++ b/brain-jogging.py
@@ -51,6 +51,28 @@ def generate_math_problem():
         return format_and_return(a, b, operation, a // b)
 
 def create_brain_jogging_pdf(filename):
+    """
+    Creates a brain jogging PDF with math problems and saves it to the specified filename.
+
+    The PDF contains 20 rows with 4 math problems per row, chosen randomly from addition, subtraction, multiplication, and division.
+    The PDF has two pages: the first page contains only the math problems, and the second page includes the problems along with their results.
+
+    Args:
+        filename (str): The output PDF filename.
+
+    Dependencies:
+        - reportlab.lib.pagesizes.A4
+        - reportlab.platypus.SimpleDocTemplate
+        - reportlab.platypus.Paragraph
+        - reportlab.platypus.Spacer
+        - reportlab.platypus.Table
+        - reportlab.platypus.PageBreak
+        - reportlab.lib.colors
+        - reportlab.platypus.TableStyle
+        - reportlab.lib.styles.getSampleStyleSheet
+        - reportlab.pdfbase.pdfmetrics
+        - reportlab.pdfbase.ttfonts.TTFont
+    """
     problems = [[generate_math_problem() for _ in range(4)] for _ in range(20)]
     data = [[problem[0] for problem in row] for row in problems]
     data_with_results = [[f"{problem[0]} {problem[1]}" for problem in row] for row in problems]