#14178: DEV: Update Boschloo Exact test
#14264: REL: prepare for SciPy 1.7.1
#14283: BUG: fix refguide-check namedtuple handling
#14303: FIX: Check for None before calling str methods
#14327: BUG: medfilt can access beyond the end of an array
#14355: BUG: KDTree balanced_tree is unbalanced for degenerate data
#14368: BUG: avoid large cython global variable in function
#14384: BUG: Reference count leak in distance_pybind
#14397: DOC/CI: do not allow sphinx 4.1.
#14417: DOC/CI: pin sphinx to !=4.1.0
#14460: DOC: add required scipy version to kwarg
#14466: MAINT: 1.7.1 backports (round 1)
#14508: MAINT: bump scipy-mathjax
#14509: MAINT: 1.7.1 backports (round 2)