Fix circular import by importing modelcontext from pymc.model.core

Author: aman-coder03

pymc/distributions/shape_utils.py

@@ -33,7 +33,7 @@
 from pytensor.tensor.type_other import NoneTypeT
 from pytensor.tensor.variable import TensorVariable
 
-from pymc.model import modelcontext
+from pymc.model.core import modelcontext
 from pymc.pytensorf import convert_observed_data
 
 __all__ = [