

from __future__ import annotations

__A      		=     list[list[int]]

# assigning initial values to the grid
__A      		=     [
    [3, 0, 6, 5, 0, 8, 4, 0, 0],
    [5, 2, 0, 0, 0, 0, 0, 0, 0],
    [0, 8, 7, 0, 0, 0, 0, 3, 1],
    [0, 0, 3, 0, 1, 0, 0, 8, 0],
    [9, 0, 0, 8, 6, 3, 0, 0, 5],
    [0, 5, 0, 0, 9, 0, 6, 0, 0],
    [1, 3, 0, 0, 0, 0, 2, 5, 0],
    [0, 0, 0, 0, 0, 0, 0, 7, 4],
    [0, 0, 5, 2, 0, 6, 3, 0, 0],
]

# a grid with no solution
__A      		=     [
    [5, 0, 6, 5, 0, 8, 4, 0, 3],
    [5, 2, 0, 0, 0, 0, 0, 0, 2],
    [1, 8, 7, 0, 0, 0, 0, 3, 1],
    [0, 0, 3, 0, 1, 0, 0, 8, 0],
    [9, 0, 0, 8, 6, 3, 0, 0, 5],
    [0, 5, 0, 0, 9, 0, 6, 0, 0],
    [1, 3, 0, 0, 0, 0, 2, 5, 0],
    [0, 0, 0, 0, 0, 0, 0, 7, 4],
    [0, 0, 5, 2, 0, 6, 3, 0, 0],
]



def 				snake_case_(_UpperCamelCase			,	_UpperCamelCase			,	_UpperCamelCase			,	_UpperCamelCase					)							->     bool:



  """simple docstring"""






  for i in range(9					):
    if grid[row][i] == n or grid[i][column] == n:
      return False

  for i in range(3					):
    for j in range(3					):
      if grid[(row - row % 3) + i][(column - column % 3) + j] == n:
        return False

  return True



def 				snake_case_(_UpperCamelCase					)							->     tuple[int, int] | None:



  """simple docstring"""






  for i in range(9					):
    for j in range(9					):
      if grid[i][j] == 0:
        return i, j
  return None



def 				snake_case_(_UpperCamelCase					)							->     Matrix | None:



  """simple docstring"""






  if location := find_empty_location(_UpperCAmelCase					):
    _snake_case						=							location
  else:
    # If the location is ``None``, then the grid is solved.
    return grid

  for digit in range(1			,	10					):
    if is_safe(_UpperCAmelCase			,	_UpperCAmelCase			,	_UpperCAmelCase			,	_UpperCAmelCase					):
      _snake_case						=							digit

      if sudoku(_UpperCAmelCase					) is not None:
        return grid

      _snake_case						=							0

  return None



def 				snake_case_(_UpperCamelCase					)							->     None:



  """simple docstring"""






  for row in grid:
    for cell in row:
      print(_UpperCAmelCase			,	end=''' '''					)
    print()


if __name__ == "__main__":
 # make a copy of grid so that you can compare with the unmodified grid
 for example_grid in (initial_grid, no_solution):
  print('''\nExample grid:\n''' + '''=''' * 20)
  print_solution(example_grid)
  print('''\nExample grid solution:''')
  __A      		=     sudoku(example_grid)
  if solution is not None:
   print_solution(solution)
  else:
   print('''Cannot find a solution.''')




__A      		=     '''ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'''



def 				snake_case_(_UpperCamelCase					)							->     bytes:



  """simple docstring"""






  if not isinstance(_UpperCamelCase			,	_UpperCamelCase					):
    _snake_case						=							F"""a bytes-like object is required, not '{data.__class__.__name__}'"""
    raise TypeError(_UpperCamelCase					)

  _snake_case						=							''''''.join(bin(_UpperCamelCase					)[2:].zfill(8					) for byte in data					)

  _snake_case						=							len(_UpperCamelCase					) % 6 != 0

  if padding_needed:
    # The padding that will be added later
    _snake_case						=							b'''=''' * ((6 - len(_UpperCamelCase					) % 6) // 2)

    # Append binary_stream with arbitrary binary digits (0's by default) to make its
    # length a multiple of 6.
    binary_stream += "0" * (6 - len(_UpperCamelCase					) % 6)
  else:
    _snake_case						=							b''''''

  # Encode every 6 binary digits to their corresponding Base64 character
  return (
      "".join(
          B64_CHARSET[int(binary_stream[index : index + 6]			,	2					)]
          for index in range(0			,	len(_UpperCamelCase					)			,	6					)					).encode()
      + padding
  )



def 				snake_case_(_UpperCamelCase					)							->     bytes:



  """simple docstring"""






  if not isinstance(_UpperCamelCase			,	_UpperCamelCase					) and not isinstance(_UpperCamelCase			,	_UpperCamelCase					):
    _snake_case						=							(
        '''argument should be a bytes-like object or ASCII string, '''
        F"""not '{encoded_data.__class__.__name__}'"""
    )
    raise TypeError(_UpperCamelCase					)

  # In case encoded_data is a bytes-like object, make sure it contains only
  # ASCII characters so we convert it to a string object
  if isinstance(_UpperCamelCase			,	_UpperCamelCase					):
    try:
      _snake_case						=							encoded_data.decode('''utf-8'''					)
    except UnicodeDecodeError:
      raise ValueError('''base64 encoded data should only contain ASCII characters'''					)

  _snake_case						=							encoded_data.count('''='''					)

  # Check if the encoded string contains non base64 characters
  if padding:
    assert all(
        char in B64_CHARSET for char in encoded_data[:-padding]					), "Invalid base64 character(s) found."
  else:
    assert all(
        char in B64_CHARSET for char in encoded_data					), "Invalid base64 character(s) found."

  # Check the padding
  assert len(_UpperCamelCase					) % 4 == 0 and padding < 3, "Incorrect padding"

  if padding:
    # Remove padding if there is one
    _snake_case						=							encoded_data[:-padding]

    _snake_case						=							''''''.join(
        bin(B64_CHARSET.index(_UpperCamelCase					)					)[2:].zfill(6					) for char in encoded_data					)[: -padding * 2]
  else:
    _snake_case						=							''''''.join(
        bin(B64_CHARSET.index(_UpperCamelCase					)					)[2:].zfill(6					) for char in encoded_data					)

  _snake_case						=							[
      int(binary_stream[index : index + 8]			,	2					)
      for index in range(0			,	len(_UpperCamelCase					)			,	8					)
  ]

  return bytes(_UpperCamelCase					)


if __name__ == "__main__":
 import doctest

 doctest.testmod()

