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Python - Making your own functions to CRUD a list

I re-implemented the logic behind the functions that you get with lists in Python. Need not do this. But just to understand how things work behind the scene.
class MyArray:
def __init__(self):
self.values = []
self.length = 0

def display(self):
print("Displaying")
for i in range(0, self.length):
print(self.values[i])

def add(self, value):
self.values.append(value)
self.length += 1
return self.values
def add_at(self, index, value):
self.add(self.values[-1])
for i in reversed(range(index, self.length)):
self.values[i]=self.values[i-1]
self.values[index] = value

def pop(self):
self.length -= 1
return self.values.pop(-1)

def remove_at(self, index):
for i in range(index, self.length-1):
self.values[i]=self.values[i+1]
self.pop()


obj = MyArray()
print("Length {}".format(obj.length))

obj.add('hi')
print(obj.values)
print("Length {}".format(obj.length))

obj.add('how')
print(obj.values)
print("Length {}".format(obj.length))

obj.add('are')
print(obj.values)
print("Length {}".format(obj.length))

obj.add('you')
print(obj.values)
print("Length {}".format(obj.length))

obj.pop()
obj.display()
print("Length {}".format(obj.length))

print(obj.values)
obj.remove_at(0)
obj.display()
print("Length {}".format(obj.length))

print(obj.values)
print("Length {}".format(obj.length))

obj.add('hello')
print(obj.values)
print("Length {}".format(obj.length))

obj.add('welcome')
print(obj.values)
print("Length {}".format(obj.length))

obj.add('to')
print(obj.values)
print("Length {}".format(obj.length))

obj.add('PyVinit')
print(obj.values)

print("Length {}".format(obj.length))
obj.display()
obj.add_at(2, 'a')
obj.display()
print("Length {}".format(obj.length))

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