diff --git a/bindings/python/unicorn/unicorn.py b/bindings/python/unicorn/unicorn.py
index ae672227..95f927dc 100644
--- a/bindings/python/unicorn/unicorn.py
+++ b/bindings/python/unicorn/unicorn.py
@@ -60,37 +60,41 @@ def _setup_prototype(lib, fname, restype, *argtypes):
     getattr(lib, fname).restype = restype
     getattr(lib, fname).argtypes = argtypes
 
-_setup_prototype(_uc, "uc_version", ctypes.c_int, ctypes.POINTER(ctypes.c_int), ctypes.POINTER(ctypes.c_int))
+ucerr = ctypes.c_int
+ucengine = ctypes.c_void_p
+uc_hook_h = ctypes.c_size_t
+
+_setup_prototype(_uc, "uc_version", ucerr, ctypes.POINTER(ctypes.c_int), ctypes.POINTER(ctypes.c_int))
 _setup_prototype(_uc, "uc_arch_supported", ctypes.c_bool, ctypes.c_int)
-_setup_prototype(_uc, "uc_open", ctypes.c_int, ctypes.c_uint, ctypes.c_uint, ctypes.POINTER(ctypes.c_size_t))
-_setup_prototype(_uc, "uc_close", ctypes.c_int, ctypes.POINTER(ctypes.c_size_t))
-_setup_prototype(_uc, "uc_strerror", ctypes.c_char_p, ctypes.c_int)
-_setup_prototype(_uc, "uc_errno", ctypes.c_int, ctypes.c_size_t)
-_setup_prototype(_uc, "uc_reg_read", ctypes.c_int, ctypes.c_size_t, ctypes.c_int, ctypes.c_void_p)
-_setup_prototype(_uc, "uc_reg_write", ctypes.c_int, ctypes.c_size_t, ctypes.c_int, ctypes.c_void_p)
-_setup_prototype(_uc, "uc_mem_read", ctypes.c_int, ctypes.c_size_t, ctypes.c_uint64, ctypes.POINTER(ctypes.c_char), ctypes.c_size_t)
-_setup_prototype(_uc, "uc_mem_write", ctypes.c_int, ctypes.c_size_t, ctypes.c_uint64, ctypes.POINTER(ctypes.c_char), ctypes.c_size_t)
-_setup_prototype(_uc, "uc_emu_start", ctypes.c_int, ctypes.c_size_t, ctypes.c_uint64, ctypes.c_uint64, ctypes.c_uint64, ctypes.c_size_t)
-_setup_prototype(_uc, "uc_emu_stop", ctypes.c_int, ctypes.c_size_t)
-_setup_prototype(_uc, "uc_hook_del", ctypes.c_int, ctypes.c_size_t, ctypes.POINTER(ctypes.c_size_t))
-_setup_prototype(_uc, "uc_mem_map", ctypes.c_int, ctypes.c_size_t, ctypes.c_uint64, ctypes.c_size_t, ctypes.c_uint32)
+_setup_prototype(_uc, "uc_open", ucerr, ctypes.c_uint, ctypes.c_uint, ctypes.POINTER(ucengine))
+_setup_prototype(_uc, "uc_close", ucerr, ucengine)
+_setup_prototype(_uc, "uc_strerror", ctypes.c_char_p, ucerr)
+_setup_prototype(_uc, "uc_errno", ucerr, ucengine)
+_setup_prototype(_uc, "uc_reg_read", ucerr, ucengine, ctypes.c_int, ctypes.c_void_p)
+_setup_prototype(_uc, "uc_reg_write", ucerr, ucengine, ctypes.c_int, ctypes.c_void_p)
+_setup_prototype(_uc, "uc_mem_read", ucerr, ucengine, ctypes.c_uint64, ctypes.POINTER(ctypes.c_char), ctypes.c_size_t)
+_setup_prototype(_uc, "uc_mem_write", ucerr, ucengine, ctypes.c_uint64, ctypes.POINTER(ctypes.c_char), ctypes.c_size_t)
+_setup_prototype(_uc, "uc_emu_start", ucerr, ucengine, ctypes.c_uint64, ctypes.c_uint64, ctypes.c_uint64, ctypes.c_size_t)
+_setup_prototype(_uc, "uc_emu_stop", ucerr, ucengine)
+_setup_prototype(_uc, "uc_hook_del", ucerr, ucengine, uc_hook_h)
+_setup_prototype(_uc, "uc_mem_map", ucerr, ucengine, ctypes.c_uint64, ctypes.c_size_t, ctypes.c_uint32)
 
 # uc_hook_add is special due to variable number of arguments
 _uc.uc_hook_add = getattr(_uc, "uc_hook_add")
 _uc.uc_hook_add.restype = ctypes.c_int
 
-UC_HOOK_CODE_CB = ctypes.CFUNCTYPE(None, ctypes.c_size_t, ctypes.c_uint64, ctypes.c_size_t, ctypes.c_void_p)
-UC_HOOK_MEM_INVALID_CB = ctypes.CFUNCTYPE(ctypes.c_bool, ctypes.c_size_t, ctypes.c_int, \
+UC_HOOK_CODE_CB = ctypes.CFUNCTYPE(None, ucengine, ctypes.c_uint64, ctypes.c_size_t, ctypes.c_void_p)
+UC_HOOK_MEM_INVALID_CB = ctypes.CFUNCTYPE(ctypes.c_bool, ucengine, ctypes.c_int, \
         ctypes.c_uint64, ctypes.c_int, ctypes.c_int64, ctypes.c_void_p)
-UC_HOOK_MEM_ACCESS_CB = ctypes.CFUNCTYPE(None, ctypes.c_size_t, ctypes.c_int, \
+UC_HOOK_MEM_ACCESS_CB = ctypes.CFUNCTYPE(None, ucengine, ctypes.c_int, \
         ctypes.c_uint64, ctypes.c_int, ctypes.c_int64, ctypes.c_void_p)
-UC_HOOK_INTR_CB = ctypes.CFUNCTYPE(None, ctypes.c_size_t, ctypes.c_uint32, \
+UC_HOOK_INTR_CB = ctypes.CFUNCTYPE(None, ucengine, ctypes.c_uint32, \
         ctypes.c_void_p)
-UC_HOOK_INSN_IN_CB = ctypes.CFUNCTYPE(ctypes.c_uint32, ctypes.c_size_t, ctypes.c_uint32, \
+UC_HOOK_INSN_IN_CB = ctypes.CFUNCTYPE(ctypes.c_uint32, ucengine, ctypes.c_uint32, \
         ctypes.c_int, ctypes.c_void_p)
-UC_HOOK_INSN_OUT_CB = ctypes.CFUNCTYPE(None, ctypes.c_size_t, ctypes.c_uint32, \
+UC_HOOK_INSN_OUT_CB = ctypes.CFUNCTYPE(None, ucengine, ctypes.c_uint32, \
         ctypes.c_int, ctypes.c_uint32, ctypes.c_void_p)
-UC_HOOK_INSN_SYSCALL_CB = ctypes.CFUNCTYPE(None, ctypes.c_size_t, ctypes.c_void_p)
+UC_HOOK_INSN_SYSCALL_CB = ctypes.CFUNCTYPE(None, ucengine, ctypes.c_void_p)
 
 
 # access to error code via @errno of UcError
@@ -130,7 +134,7 @@ class Uc(object):
             raise UcError(UC_ERR_VERSION)
 
         self._arch, self._mode = arch, mode
-        self._uch = ctypes.c_size_t()
+        self._uch = ctypes.c_void_p()
         status = _uc.uc_open(arch, mode, ctypes.byref(self._uch))
         if status != UC_ERR_OK:
             self._uch = None
@@ -144,7 +148,8 @@ class Uc(object):
     def __del__(self):
         if self._uch:
             try:
-                status = _uc.uc_close(ctypes.byref(self._uch))
+                status = _uc.uc_close(self._uch)
+                self._uch = None
                 if status != UC_ERR_OK:
                     raise UcError(status)
             except: # _uc might be pulled from under our feet
@@ -251,7 +256,7 @@ class Uc(object):
 
     # add a hook
     def hook_add(self, htype, callback, user_data=None, arg1=1, arg2=0):
-        _h2 = ctypes.c_size_t()
+        _h2 = uc_hook_h()
 
         # save callback & user_data
         self._callback_count += 1
@@ -296,8 +301,8 @@ class Uc(object):
 
     # delete a hook
     def hook_del(self, h):
-        _h = ctypes.c_size_t(h)
-        status = _uc.uc_hook_del(self._uch, ctypes.byref(_h))
+        _h = uc_hook_h(h)
+        status = _uc.uc_hook_del(self._uch, _h)
         if status != UC_ERR_OK:
             raise UcError(status)
         h = 0