diff --git a/longest_word.py b/longest_word.py
new file mode 100644
index 0000000..d525a2b
--- /dev/null
+++ b/longest_word.py
@@ -0,0 +1,58 @@
+import unittest
+import string
+import sys
+
+def find_longest_word(sentence):
+    # Remove punctuation
+    cleaned_sentence = sentence.translate(str.maketrans('', '', string.punctuation))
+    words = cleaned_sentence.split()
+    longest = ""
+
+    for word in words:
+        if len(word) > len(longest):
+            longest = word
+
+    return longest
+
+class TestFindLongestWord(unittest.TestCase):
+
+    def test_regular_sentence(self):
+        self.assertEqual(find_longest_word("Random sentences can also spur creativity"), "creativity")
+
+    def test_with_punctuation(self):
+        self.assertEqual(find_longest_word("The quick, brown fox jumped over the lazy dog."), "jumped")
+
+    def test_tie_same_length(self):
+        self.assertEqual(find_longest_word("Cat bat rat mat"), "Cat")
+
+    def test_single_word(self):
+        self.assertEqual(find_longest_word("Supercalifragilisticexpialidocious!"), "Supercalifragilisticexpialidocious")
+
+    def test_with_numbers_and_punctuation(self):
+        self.assertEqual(find_longest_word("Python 3.10 is awesome, right?"), "awesome")
+
+    def test_empty_input(self):
+        self.assertEqual(find_longest_word(""), "")
+
+    def test_only_punctuation(self):
+        self.assertEqual(find_longest_word("!!! ,,, ???"), "")
+
+def interactive_mode():
+    """Provides interactive input for the user to test the function."""
+    print("Enter sentences to find the longest word, or type 'q' to quit.")
+    while True:
+        sentence = input("Enter a sentence: ")
+        if sentence.lower() == 'q':
+            break
+        print("Longest word:", find_longest_word(sentence))
+    print("Goodbye!")
+
+
+if __name__ == '__main__':
+    # If "test" is provided as an argument, run unit tests.
+    if len(sys.argv) > 1 and sys.argv[1] == "test":
+        # Remove the "test" argument so unittest doesn't process it.
+        sys.argv.pop(1)
+        unittest.main()
+    else:
+        interactive_mode()
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