fix deprecated import. fix sympy install in noxfile.

noxfile.py

@@ -76,7 +76,8 @@ def install_pystencils_master(session: nox.Session):
 
 
 def install_sympy_master(session: nox.Session):
-    session.install("git+https://i10git.cs.fau.de/pycodegen/pystencils.git@master")
+    session.install("--upgrade", "git+https://github.com/sympy/sympy.git@master")
+
 
 @nox.session(python="3.10", tags=["qa", "code-quality"])
 def lint(session: nox.Session):

src/lbmpy/advanced_streaming/communication.py

 import itertools
-from pystencils import CreateKernelConfig, Field, Assignment, AssignmentCollection
+from pystencils import CreateKernelConfig, Field, Assignment, AssignmentCollection, Target
 from pystencils.slicing import (
     shift_slice,
     get_slice_before_ghost_layer,
@@ -14,7 +14,6 @@ from lbmpy.advanced_streaming.utility import (
     numeric_offsets,
 )
 from pystencils.datahandling import SerialDataHandling
-from pystencils.enums import Target
 from itertools import chain