def is_palindrome(word):
  """
  Checks whether a word is a palindrome.

  Args:
    word: The word to check.

  Returns:
    True if the word is a palindrome, False otherwise.
  """

  # Convert the word to lowercase and remove non-alphanumeric characters.
  word = ''.join(char.lower() for char in word if char.isalnum())

  # Check if the word is the same forwards and backwards.
  return word == word[::-1]
 _________________________________________________ 

      def is_palindrome(word):
  """
  Checks whether a word is a palindrome.

  Args:
    word: The word to check.

  Returns:
    True if the word is a palindrome, False otherwise.
  """

  # Convert the word to lowercase and remove non-alphanumeric characters.
  word = ''.join(char.lower() for char in word if char.isalnum())

  # Check if the word is the same forwards and backwards.
  return word == word[::-1]

# Unit Tests
import unittest

class TestIsPalindrome(unittest.TestCase):

  def test_empty_string(self):
    """Test with an empty string."""
    self.assertTrue(is_palindrome(""))

  def test_single_character(self):
    """Test with a single character."""
    self.assertTrue(is_palindrome("a"))

  def test_palindrome(self):
    """Test with a palindrome word."""
    self.assertTrue(is_palindrome("racecar"))

  def test_not_palindrome(self):
    """Test with a non-palindrome word."""
    self.assertFalse(is_palindrome("hello"))

  def test_case_insensitive(self):
    """Test case-insensitive palindrome."""
    self.assertTrue(is_palindrome("Racecar"))

  def test_with_spaces(self):
    """Test with spaces."""
    self.assertTrue(is_palindrome("A man, a plan, a canal: Panama"))

  def test_with_punctuation(self):
    """Test with punctuation."""
    self.assertTrue(is_palindrome("madam, I'm Adam!"))

  def test_with_numbers(self):
    """Test with numbers."""
    self.assertTrue(is_palindrome("12321"))

  def test_with_special_characters(self):
    """Test with special characters."""
    self.assertFalse(is_palindrome("!@#$%^"))

  def test_with_mixed_characters(self):
    """Test with mixed characters."""
    self.assertTrue(is_palindrome("A Toyota's a Toyota"))

if __name__ == '__main__':
  unittest.main()