python code for binary search tree

#Complete Binary Search Tree Using Python 3

class node:
    def  __init__(self,data):
        self.data=data
        self.left=None
        self.right=None

class binarytree:
    def __init__(self):
        self.root=None

#INSERT

    def insert(self,data):
        if self.root==None:				
            self.root=node(data)
        else:
            self._insert(data,self.root)
    def _insert(self,data,cur_node):
        if data<cur_node.data:
            if cur_node.left==None:			
                cur_node.left=node(data)
            else:
                self._insert(data,cur_node.left) 
        elif data>cur_node.data:			
            if cur_node.right==None:
                cur_node.right=node(data)
            else:
                self._insert(data,cur_node.right)
        else:
            print('Data In Treee Already')

#REMOVE

    def remove(self,data):
        if self.root!=None:
            self._remove(data,self.root)
    def _remove(self,data,cur_node):
        if cur_node == None:
            return cur_node
        if data<cur_node.data:
            cur_node.left=self._remove(data,cur_node.left)
        elif data>cur_node.data:
            cur_node.right=self._remove(data,cur_node.right)
        else:
            if cur_node.left is None and cur_node.right is None:
                print('Removing Leaf Node')
                if cur_node==self.root:
                    self.root=None
                del cur_node
                return None
            if cur_node.left is None:
                print('Removing None with Right Child')
                if cur_node==self.root:
                    self.root=cur_node.right
                tempnode=cur_node.right
                del cur_node
                return tempnode
            elif cur_node.right is None:
                print('Removing None with Left Child')
                if cur_node==self.root:
                    self.root=cur_node.left
                tempnode=cur_node.left
                del cur_node
                return tempnode
            print('Removing Node with 2 Children')
            tempnode=self.getpred(cur_node.left)
            cur_node.data=tempnode.data
            cur_node.left=self._remove(cur_node.data,cur_node.left)
        return cur_node
    def getpred(self,cur_node):
        if cur_node.right!=None:
            return self.getpred(cur_node.right)
        return cur_node

#INORDER TRAVERSAL

    def inorder(self):
        if self.root!=None:
            self._inorder(self.root)
    def _inorder(self,cur_node):
        if cur_node!=None:
            self._inorder(cur_node.left)
            print(cur_node.data)
            self._inorder(cur_node.right)

#PREORDER TRAVERSAL

    def preorder(self):
        if self.root!=None:
            self._preorder(self.root)
    def _preorder(self,cur_node):
        if cur_node!=None:
            print(cur_node.data)
            self._preorder(cur_node.left)
            self._preorder(cur_node.right)

#POSTORDER TRAVERSAL

    def postorder(self):
        if self.root!=None:
            self._postorder(self.root)
    def _postorder(self,cur_node):
        if cur_node!=None:
            self._postorder(cur_node.left)
            self._postorder(cur_node.right)
            print(cur_node.data)

#MINIMUM VALUE

    def minval(self):
        if self.root!=None:
            return self._minval(self.root)
    def _minval(self,cur_node):
        if cur_node.left!=None:
            return self._minval(cur_node.left)
        return cur_node.data

#MAXIMUM VALUE

    def maxval(self):
        if self.root!=None:
            return self._maxval(self.root)
    def _maxval(self,cur_node):
        if cur_node.right!=None:
            return self._maxval(cur_node.right)
        return cur_node.data

tree=binarytree()

tree.insert(100)
tree.insert(90)					#			 100
tree.insert(110)				#			/	\
tree.insert(95)					#          90   110
tree.insert(30)					#		  /  \
								#		30    95 
tree.remove(110)
tree.remove(90)

tree.inorder()
#tree.preorder()
#tree.postorder()

print(tree.minval())
print(tree.maxval())