This last answer (user7711283) is working under windows with a minor fix:

class RAWMOUSE(ctypes.Structure):
_fields_ = [
    ("usFlags", ctypes.c_ushort),
    #("ulButtons", ctypes.c_ulong),
    ("usButtonFlags", ctypes.c_ushort),
    ("usButtonData", ctypes.c_ushort),
    ("ulRawButtons", ctypes.c_ulong),
    ("lLastX", ctypes.c_long),
    ("lLastY", ctypes.c_long),
    ("ulExtraInformation", ctypes.c_ulong)
]

Indeed, as the struct is a union, you need to comment either "usButtons" or both "usButtonData" and "usButtonFlags"