Coordinates of the last cell in a Matrix on which performing given operations exits from the Matrix.py

class Solution():
    def issafe(self, m, n, i, j):
     
      if (i < 0):
        return False
      if (j < 0):
        return False
      if (i >= m):
        return False
      if (j >= n):
        return False
     
      return True

    def endPoints(self, matrix, m, n):
     
      i = 0
      j = 0
      current_i = 0
      current_j = 0
      current_d = 'r'
     
      rcd = {'l':'u','u':'r','r':'d','d':'l'}
     
      while (self.issafe(m, n, i, j)):
        current_i = i
        current_j = j
     
        if (matrix[i][j] == 1):
     
          move_in = rcd.get(current_d)
          matrix[i][j] = 0
     
          if (move_in == 'u'):
            i -= 1
          elif(move_in == 'd'):
            i += 1
          elif(move_in == 'l'):
            j -= 1
          elif(move_in == 'r'):
            j += 1
     
          current_d = move_in
     
        else:
          if (current_d == 'u'):
            i -= 1
          elif(current_d == 'd'):
            i += 1
          elif(current_d == 'l'):
            j -= 1
          elif(current_d == 'r'):
            j += 1
     
      return [current_i, current_j]