Quick Python BST

bst.py

class Node(object):
  def __init__(self,value):
    self.value = value
    self.right = None
    self.left = None

  def add(self, x):
    if x.value == self.value: return "Value already in tree"

    elif x.value < self.value:
      if self.left: return self.left.add(x)
      else: self.left = x
    elif x.value > self.value:
      if self.right: return self.right.add(x)
      else: self.right = x

  def find(self, x):
    if x == self.value: return self.value

    elif x < self.value:
      if self.left: return self.left.find(x)
      else: return "Value not in tree."
    elif x > self.value:
      if self.right: return self.right.find(x)
      else: return "Value not in tree."

  def remove(self, x):
    if self.value == x: return "Cannot delete root."

    elif x < self.value:
      if self.left: 
       if self.left.value == x:
         if self.left.left:
           if self.left.right: self.left.left.add(self.left.right)
           self.left = self.left.left
            
         elif self.left.right:
           if self.left.left: self.left.right.add(self.left.left)
           self.left = self.left.right

         else: return

       else:
         self.left.remove(x)
      else:
       return "Value not in tree"
    elif x > self.value:
      if self.right: 
        if self.right.value == x:
          if self.right.left:
            if self.right.right: self.right.left.add(self.right.right)
            self.right = self.right.left
            
          elif self.right.right:
            if self.right.left: self.right.right.add(self.right.left)
            self.right = self.right.right

          else: return
          
        else:
          self.left.remove(x)
      else:
        return "Value not in tree"


if __name__ == "__main__":
  root = Node(5)
  root.add(Node(4))
  root.add(Node(7))
  root.add(Node(6))
  root.add(Node(10))
  root.add(Node(3))
  root.add(Node(1))

  root.remove(4)
  root.remove(7)

  print root.find(10)