what is pascal triangle in python code example

Example: pascal's triangle python

def solve(A):
    pascals_triangle = []

    for i in range(A):
        pascals_triangle.append([1]*(i+1))
  
    for i in range(2,A):
        for j in range(1,i):
            pascals_triangle[i][j] = pascals_triangle[i-1][j-1] + pascals_triangle[i-1][j]

    return pascals_triangle