message: Update toeplitz-matrix.py
diff: # Time: O(m * n)
  # Space: O(1)
  +# A matrix is Toeplitz if every diagonal from top-left to bottom-right has the same element.
  +# Now given an M x N matrix, return True if and only if the matrix is Toeplitz.
  +#
  +# Example 1:
  +#
  +# Input: matrix = [[1,2,3,4],[5,1,2,3],[9,5,1,2]]
  +# Output: True
  +# Explanation:
  +# 1234
  +# 5123
  +# 9512
  +#
  +# In the above grid, the diagonals are
  +# "[9]", "[5, 5]", "[1, 1, 1]", "[2, 2, 2]", "[3, 3]", "[4]",
  +# and in each diagonal all elements are the same, so the answer is True.
  +#
  +# Example 2:
  +#
  +# Input: matrix = [[1,2],[2,2]]
  +# Output: False
  +# Explanation:
  +# The diagonal "[1, 2]" has different elements.
  +#
  +# Note:
  +# - matrix will be a 2D array of integers.
  +# - matrix will have a number of rows and columns in range [1, 20].
  +# - matrix[i][j] will be integers in range [0, 99].
  +
  class Solution(object):
  def isToeplitzMatrix(self, matrix):
  """
  