Fix deepcopying on Python 3.11

Python 3.11 added object.__setstate__ (https://github.com/python/cpython/commit/884eba3c76916889fd6bff3b37b8552bfb4f9566), which breaks our fix for #40 (closed), but only on Sympy version 1.11 because that version added sympy.Basic.__setstate__ (https://github.com/sympy/sympy/commit/24e1e1a2ea4e3952c577d36138f31780b7548512). The updated fix is actually more logical (because it actually does what the comment says), so hopefully it will survive future version updates better.

This fixes both the AttributeError: 'tuple' object has no attribute 'items' issue which we already have a fix for in !327 (closed), and the sp.Pow issue that came up next.

Tested with Python 3.10 and 3.11 and Sympy 1.9 and 1.11.

@holzer, you'll need to merge manually because of builds failing due to !327 (closed).

pystencils/typing/utilities.py

@@ -187,18 +187,15 @@ def get_type_of_expression(expr,
 
 # Fix for sympy versions from 1.9
 sympy_version = sp.__version__.split('.')
-if int(sympy_version[0]) * 100 + int(sympy_version[1]) >= 109:
+sympy_version_int = int(sympy_version[0]) * 100 + int(sympy_version[1])
+if sympy_version_int >= 109:
     # __setstate__ would bypass the contructor, so we remove it
-    sp.Number.__getstate__ = sp.Basic.__getstate__
-    del sp.Basic.__getstate__
-
-    class FunctorWithStoredKwargs:
-        def __init__(self, func, **kwargs):
-            self.func = func
-            self.kwargs = kwargs
-
-        def __call__(self, *args):
-            return self.func(*args, **self.kwargs)
+    if sympy_version_int >= 111:
+        del sp.Basic.__setstate__
+        del sp.Symbol.__setstate__
+    else:
+        sp.Number.__getstate__ = sp.Basic.__getstate__
+        del sp.Basic.__getstate__
 
     # __reduce_ex__ would strip kwargs, so we override it
     def basic_reduce_ex(self, protocol):
@@ -210,9 +207,7 @@ if int(sympy_version[0]) * 100 + int(sympy_version[1]) >= 109:
             state = self.__getstate__()
         else:
             state = None
-        return FunctorWithStoredKwargs(type(self), **kwargs), args, state
-
-    sp.Number.__reduce_ex__ = sp.Basic.__reduce_ex__
+        return partial(type(self), **kwargs), args, state
     sp.Basic.__reduce_ex__ = basic_reduce_ex