Add code for 2015 advent that I did historically.

day_5/part_1.py

@@ -0,0 +1,33 @@
+import re
+
+
+forbidden_sequences = [ "ab", "cd", "pq", "xy" ]
+double_letter_pattern = r"(?P<char>[A-Za-z])(?P=char)"
+
+
+def has_three_vowels(string):
+	vowel_count = 0
+	for char in string:
+		if char in "aeiou":
+			vowel_count += 1
+	return vowel_count >= 3
+
+
+def has_double_letter(string):
+	return re.search(double_letter_pattern, string) != None
+
+
+def no_forbidden_sequences(string):
+	for sequence in forbidden_sequences:
+		if sequence in string:
+			return False
+	return True
+
+
+total_nice_lines = 0
+data = open("input", "r")
+for line in data:
+	if has_three_vowels(line) and has_double_letter(line) and no_forbidden_sequences(line):
+		total_nice_lines += 1
+data.close()
+print(f"Total Nice Lines: {total_nice_lines}")