BrainFuck Interpreter in Python

bf_interpreter.py

valid_commands = ['>', '<', '+', '-', '[', ']', ',', '.']

clean = lambda raw_script: list(filter(lambda x: x in valid_commands, raw_script))

def parse_square_brackets(script):
  stack = []
  brackets_map = {}
  for index, command in enumerate(script):
    if command == '[': 
      stack.append(index)
      brackets_map[index] = None
    elif command == ']': 
      bracket_start_index = stack.pop(len(stack) - 1)
      brackets_map[index] = bracket_start_index
      brackets_map[bracket_start_index] = index

  return brackets_map

def execute_command(command, code_pointer, brackets_map, tape, data_pointer):
  if   command == '>': data_pointer += 1
  elif command == '<': data_pointer -= 1
  elif command == '+': tape[data_pointer] += 1
  elif command == '-': tape[data_pointer] -= 1
  elif command == '[': 
    if tape[data_pointer] == 0:
      code_pointer = brackets_map[code_pointer] 
  elif command == ']': 
    if tape[data_pointer] > 0:
      code_pointer = brackets_map[code_pointer]
  elif command == '.': print (chr(tape[data_pointer]))
  elif command == ',': tape[data_pointer] = ord(input('i/p: '))
  return code_pointer + 1, data_pointer, tape

while True:
  tape = [0 for _ in range(30000)]
  data_pointer = 0
  script = clean(list(input('yo: ')))
  script_length = len(script)
  brackets_map = parse_square_brackets(script)
  code_pointer = 0
  while code_pointer < script_length:
    command = script[code_pointer]
    code_pointer, data_pointer, tape = execute_command(command, code_pointer, brackets_map, tape, data_pointer)
  print (tape[:17])