input: Write a function to create a Python class called StringComparator that receives two strings. The class should have methods for comparing the strings and returning whether they are equal, different, or similar up to a provided threshold.
  
  class StringComparator:
  
   def __init__(self, string1, string2):
    self.string1 = string1
    self.string2 = string2
  
   def is_equal(self):
    return self.string1 == self.string2
  
   def is_different(self):
    return self.string1 != self.string2
  
   def is_similar(self, threshold=0.5):
    distance = edit_distance(self.string1, self.string2)
    max_length = max(len(self.string1), len(self.string2))
  
    return distance / max_length < threshold
  
  assert StringComparator("hello", "hello").is_equal()==True
  assert StringComparator("hello", "hi").is_equal()==False
  assert StringComparator("hello", "hello").is_different()==False
  assert StringComparator("hello", "hi").is_different()==True
  assert StringComparator("hello", "hxllo").is_similar()==True
  assert StringComparator("hello", "hi").is_similar()==False
output: def edit_distance(str1, str2):
      m, n = len(str1), len(str2)
      dp = [[0] * (n + 1) for _ in range(m + 1)]
      
      for i in range(m + 1):
          for j in range(n + 1):
              if i == 0:
                  dp[i][j] = j
              elif j == 0:
                  dp[i][j] = i
              elif str1[i-1] == str2[j-1]:
                  dp[i][j] = dp[i-1][j-1]
              else:
                  dp[i][j] = 1 + min(dp[i-1][j], dp[i][j-1], dp[i-1][j-1])
      
      return dp[m][n]
  
  class StringComparator:
  
   def __init__(self, string1, string2):
    self.string1 = string1
    self.string2 = string2
  
   def is_equal(self):
    return self.string1 == self.string2
  
   def is_different(self):
    return self.string1 != self.string2
  
   def is_similar(self, threshold=0.5):
    distance = edit_distance(self.string1, self.string2)
    max_length = max(len(self.string1), len(self.string2))
  
    return distance / max_length < threshold