[Python] Python Append Function Malfunctioning

I am using trinket.io, an online IDE for python3. I currently do not have access to any other IDEs for download. I am trying to create a numpy array using numerous iterative and conditional statements. When I print each list, I receive the correct results that I am expecting but when I append it to the array, it results in very weird results.

This is my code:

import numpy as np
import matplotlib.pyplot as plt
from sympy import *

x = Symbol('x')
y = Function('f')(x)

#Equation is ay_(n-1) + by_n + cy_(n+1) = d
a = 3
b = 4
c = 6
d = 4

#Final row equation: ey_(n-2)+fy_(n-1)+gy_(n) = d
e = 5
f = 3
g = 7
#Timestep
h = 0.2

#Initialize variables
y_0 = 0
final_point = 1


array = []
row = []
i = 1
array_row_size = int(final_point / h)
array_column_size = array_row_size + 1

for i in range(1,array_row_size+1):
row.clear()
if i == 1:
row.append(b)
row.append(c)
for j in range(2, array_column_size-1):
row.append(0)
row.append(d)
elif i == 2:
row.append(a)
row.append(b)
row.append(c)
for j in range(3, array_column_size-1):
row.append(0)
row.append(d)
elif i < (array_column_size - 1) and i>2:
for j in range(2,i):
row.append(0)
row.append(a)
row.append(b)
row.append(c)
for j in range(i+1, array_column_size-1):
row.append(0)
row.append(d)
else:
for j in range(1, array_column_size-3):
row.append(0)
row.append(e)
row.append(f)
row.append(g)
row.append(d)
array.append(row)
print("Row:", row)
print("Array", array)

i += 1

#print(array)


and these are the results:

Row: [4, 6, 0, 0, 0, 4]
Array [[4, 6, 0, 0, 0, 4]]
Row: [3, 4, 6, 0, 0, 4]
Array [[3, 4, 6, 0, 0, 4], [3, 4, 6, 0, 0, 4]]
Row: [0, 3, 4, 6, 0, 4]
Array [[0, 3, 4, 6, 0, 4], [0, 3, 4, 6, 0, 4], [0, 3, 4, 6, 0, 4]]
Row: [0, 0, 3, 4, 6, 4]
Array [[0, 0, 3, 4, 6, 4], [0, 0, 3, 4, 6, 4], [0, 0, 3, 4, 6, 4], [0, 0, 3, 4, 6, 4]]
Row: [0, 0, 5, 3, 7, 4]
Array [[0, 0, 5, 3, 7, 4], [0, 0, 5, 3, 7, 4], [0, 0, 5, 3, 7, 4], [0, 0, 5, 3, 7, 4], [0, 0, 5, 3, 7, 4]]


This is obviously very different that expected since I would expect that each row would be different in the array whereas in each iteration, all the rows are being updated and they are the same.

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