Language differences
MicroPython implements a smaller subset of the standard library. To keep the firmware small, its parser also skips some of CPython’s checks, so it accepts code that CPython would reject.
For example, allows type annotations where CPython forbids them.
Python
def f(): print('test'): int
def f(): x, y: intMicroPython
def f(): print('test'): int
def f(): x, y: int