revert this too - entering paranoia mode

Author: Christopher Doris

src/Core/Py.jl

@@ -51,11 +51,6 @@ pyconvert(::Type{Py}, x::Py) = x
 
 setptr!(x::Py, ptr::C.PyPtr) = (setfield!(x, :ptr, ptr); x)
 
-incref(x::Py) = Base.GC.@preserve x (incref(getptr(x)); x)
-decref(x::Py) = Base.GC.@preserve x (decref(getptr(x)); x)
-
-Base.unsafe_convert(::Type{C.PyPtr}, x::Py) = getptr(x)
-
 const PYNULL_CACHE = Py[]
 
 """
@@ -80,7 +75,7 @@ const PyNULL = pynew()
 
 pynew(ptr::C.PyPtr) = setptr!(pynew(), ptr)
 
-pynew(x::Py) = Base.GC.@preserve x pynew(incref(getptr(x)))
+pynew(x::Py) = pynew(incref(getptr(x)))
 
 """
     pycopy!(dst::Py, src)
@@ -169,13 +164,13 @@ Base.print(io::IO, x::Py) = print(io, string(x))
 
 function Base.show(io::IO, x::Py)
     if get(io, :typeinfo, Any) == Py
-        if pyisnull(x)
+        if getptr(x) == C.PyNULL
             print(io, "NULL")
         else
             print(io, pyrepr(String, x))
         end
     else
-        if pyisnull(x)
+        if getptr(x) == C.PyNULL
             print(io, "<py NULL>")
         else
             s = pyrepr(String, x)