Assignment on searching in stack & queue - Level 1

**PROBLEM STATEMENT
Given a stack of boxes in different colors. Write a python function that accepts the stack of boxes and removes those boxes having color other than the primary colors (Red, Green and Blue) from the stack. The removed boxes should be en-queued into a new queue and returned. The original stack should have only the boxes having primary colors and the order must be maintained.
Perform case sensitive string comparison wherever necessary.
Note: Consider the queue to be of the same size as that of the original stack.**

Code: 

#lex_auth_0127667363049881603477

"""*********************Queue*****************************"""
class Queue:
    def __init__(self,max_size):

        self.__max_size=max_size
        self.__elements=[None]*self.__max_size
        self.__rear=-1
        self.__front=0

    def is_full(self):
        if(self.__rear==self.__max_size-1):
                return True
        return False

    def is_empty(self):
        if(self.__front>self.__rear):
            return True
        return False

    def enqueue(self,data):
        if(self.is_full()):
            print("Queue is full!!!")
        else:
            self.__rear+=1
            self.__elements[self.__rear]=data

    def dequeue(self):
        if(self.is_empty()):
            print("Queue is empty!!!")
        else:
            data=self.__elements[self.__front]
            self.__front+=1
            return data

    def display(self):
        for index in range(self.__front, self.__rear+1):
            print(self.__elements[index])


    def get_max_size(self):
        return self.__max_size

    #You can use the below __str__() to print the elements of the DS object while debugging
    def __str__(self):
        msg=[]
        index=self.__front
        while(index<=self.__rear):
            msg.append((str)(self.__elements[index]))
            index+=1
        msg=" ".join(msg)
        msg="Queue data(Front to Rear): "+msg
        return msg

"""*********************Stack*****************************"""
class Stack:
    def __init__(self,max_size):
        self.__max_size=max_size
        self.__elements=[None]*self.__max_size
        self.__top=-1

    def is_full(self):
        if(self.__top==self.__max_size-1):
            return True
        return False

    def is_empty(self):
        if(self.__top==-1):
            return True
        return False

    def push(self,data):
        if(self.is_full()):
            print("The stack is full!!")
        else:
            self.__top+=1
            self.__elements[self.__top]=data

    def pop(self):
        if(self.is_empty()):
            print("The stack is empty!!")
        else:
            data= self.__elements[self.__top]
            self.__top-=1
            return data

    def display(self):
        if(self.is_empty()):
            print("The stack is empty")
        else:
            index=self.__top
            while(index>=0):
                print(self.__elements[index])
                index-=1

    def get_max_size(self):
        return self.__max_size

    #You can use the below __str__() to print the elements of the DS object while debugging
    def __str__(self):
        msg=[]
        index=self.__top
        while(index>=0):
            msg.append((str)(self.__elements[index]))
            index-=1
        msg=" ".join(msg)
        msg="Stack data(Top to Bottom): "+msg
        return msg


def separate_boxes(box_stack):
    #Remove pass and write your logic here
    temp_stack=Stack(box_stack.get_max_size())
    output_queue=Queue(box_stack.get_max_size())
    while(not box_stack.is_empty()):
        data=box_stack.pop()
        if(data in ["Red","Green","Blue"]):
            temp_stack.push(data)
        else:
            output_queue.enqueue(data)
    while(not temp_stack.is_empty()):
        box_stack.push(temp_stack.pop())
    return output_queue

#Use different values for stack and test your program
box_stack=Stack(8)
box_stack.push("Red")
box_stack.push("Magenta")
box_stack.push("Yellow")
box_stack.push("Red")
box_stack.push("Orange")
box_stack.push("Green")
box_stack.push("White")
box_stack.push("Purple")
print("Boxes in the stack:")
box_stack.display()
result=separate_boxes(box_stack)
print()
print("Boxes in the stack after modification:")
box_stack.display()
print("Boxes in the queue:")
result.display()