Fix broken import of sp_sum

[PatrickRobotham]

sp_sum has been moved in pytensor from pytensor.sparse.basic to pytensor.sparse.math

The higher level module pytensor.sparse exports this function.

Description

Related Issue

• Closes BUG: Pymc is not compatible with latest pytensor #7983
• Related to #

Checklist

• Checked that the pre-commit linting/style checks pass
• Included tests that prove the fix is effective or that the new feature works
• Added necessary documentation (docstrings and/or example notebooks)
• If you are a pro: each commit corresponds to a relevant logical change

Type of change

• New feature / enhancement
• Bug fix
• Documentation
• Maintenance
• Other (please specify):

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.49%. Comparing base (87f80f9) to head (ef352dc).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #7984   +/-   ##
=======================================
  Coverage   91.49%   91.49%           
=======================================
  Files         116      116           
  Lines       18963    18964    +1     
=======================================
+ Hits        17350    17351    +1     
  Misses       1613     1613           

Files with missing lines	Coverage Δ
pymc/distributions/multivariate.py	93.92% <100.00%> (+<0.01%)	⬆️

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[ricardoV94]

Didn't notice the open PR, I left a comment on the original issue. PyMC main should be compatible with the pinned PyTensor dependency not its main branch. We'll be doing a new PyTensor release soon and follow with update on the PyMC side

[zwelitunyiswa]

@ricardoV94 I was trying the new version of Pytensor today and ran into the same issue.

`---------------------------------------------------------------------------
ImportError Traceback (most recent call last)
Cell In[1], line 1
----> 1 import pymc as pm

File ~/Documents/data_science/pixi_environments/pymc_dev_20251217/.pixi/envs/default/lib/python3.13/site-packages/pymc/init.py:50
45 pytensor.config.gcc__cxxflags = augmented
48 __set_compiler_flags()
---> 50 from pymc import _version, gp, math, ode, sampling
51 from pymc.backends import *
52 from pymc.blocking import *

File ~/Documents/data_science/pixi_environments/pymc_dev_20251217/.pixi/envs/default/lib/python3.13/site-packages/pymc/sampling/init.py:18
15 """MCMC samplers."""
17 from pymc.sampling.deterministic import compute_deterministics
---> 18 from pymc.sampling.forward import *
19 from pymc.sampling.mcmc import *

File ~/Documents/data_science/pixi_environments/pymc_dev_20251217/.pixi/envs/default/lib/python3.13/site-packages/pymc/sampling/forward.py:55
53 from pymc.backends.base import MultiTrace
54 from pymc.blocking import PointType
---> 55 from pymc.distributions.shape_utils import change_dist_size
56 from pymc.model import Model, modelcontext
57 from pymc.progress_bar import CustomProgress, default_progress_theme

File ~/Documents/data_science/pixi_environments/pymc_dev_20251217/.pixi/envs/default/lib/python3.13/site-packages/pymc/distributions/init.py:88
70 from pymc.distributions.distribution import (
71 Continuous,
72 DiracDelta,
(...) 75 SymbolicRandomVariable,
76 )
77 from pymc.distributions.mixture import (
78 HurdleGamma,
79 HurdleLogNormal,
(...) 86 ZeroInflatedPoisson,
87 )
---> 88 from pymc.distributions.multivariate import (
89 CAR,
90 ICAR,
91 Dirichlet,
92 DirichletMultinomial,
93 KroneckerNormal,
94 LKJCholeskyCov,
95 LKJCorr,
96 MatrixNormal,
97 Multinomial,
98 MvNormal,
99 MvStudentT,
100 OrderedMultinomial,
101 StickBreakingWeights,
102 Wishart,
103 WishartBartlett,
104 ZeroSumNormal,
105 )
106 from pymc.distributions.simulator import Simulator
107 from pymc.distributions.timeseries import (
108 AR,
109 GARCH11,
(...) 114 RandomWalk,
115 )

File ~/Documents/data_science/pixi_environments/pymc_dev_20251217/.pixi/envs/default/lib/python3.13/site-packages/pymc/distributions/multivariate.py:28
26 from pytensor.graph.op import Op
27 from pytensor.raise_op import Assert
---> 28 from pytensor.sparse.basic import DenseFromSparse, sp_sum
29 from pytensor.tensor import (
30 TensorConstant,
31 TensorVariable,
(...) 34 sigmoid,
35 )
36 from pytensor.tensor.elemwise import DimShuffle

ImportError: cannot import name 'sp_sum' from 'pytensor.sparse.basic' (/Users/zweli/Documents/data_science/pixi_environments/pymc_dev_20251217/.pixi/envs/default/lib/python3.13/site-packages/pytensor/sparse/basic.py)`