`py2bitTest/test.py::Test::testBases` fails with an `AssertionError`

[TheChymera]

[deco]~/src/py2bit ❱ pytest -vvs py2bitTest/test.py
=========================================================== test session starts ============================================================
platform linux -- Python 3.10.9, pytest-7.2.0, pluggy-1.0.0 -- /usr/bin/python3.10
cachedir: .pytest_cache
rootdir: /home/chymera/src/py2bit
plugins: pkgcore-0.12.18, mock-3.10.0, timeout-2.1.0
collected 7 items

py2bitTest/test.py::Test::testOpenClose PASSED
py2bitTest/test.py::Test::testChroms PASSED
py2bitTest/test.py::Test::testInfo PASSED
py2bitTest/test.py::Test::testSequence PASSED
py2bitTest/test.py::Test::testBases FAILED
py2bitTest/test.py::Test::testHardMaskedBlocks PASSED
py2bitTest/test.py::Test::testSoftMaskedBlocks PASSED

================================================================= FAILURES =================================================================
______________________________________________________________ Test.testBases ______________________________________________________________

self = <py2bitTest.test.Test object at 0x7f66a486c6a0>

    def testBases(self):
        tb = py2bit.open(self.fname, True)
        assert(tb.bases("chr1") == {'A': 0.08, 'C': 0.08, 'T': 0.08666666666666667, 'G': 0.08666666666666667})
        assert(tb.bases("chr1", 24, 74) == {'A': 0.12, 'C': 0.12, 'T': 0.12, 'G': 0.12})
        assert(tb.bases("chr1", 24, 74, False) == {'A': 6, 'C': 6, 'T': 6, 'G': 6})
>       assert(tb.bases("chr2", 10, 20) == {'A': 0.2, 'C': 0.2, 'T': 0.3, 'G': 0.3})
E       AssertionError: assert {'A': 0.16666666666666666, 'C': 0.16666666666666666, 'T': 0.25, 'G': 0.25} == {'A': 0.2, 'C': 0.2, 'T': 0.3, 'G': 0.3}
E         Differing items:
E         {'T': 0.25} != {'T': 0.3}
E         {'A': 0.16666666666666666} != {'A': 0.2}
E         {'C': 0.16666666666666666} != {'C': 0.2}
E         {'G': 0.25} != {'G': 0.3}
E         Full diff:
E         - {'A': 0.2, 'C': 0.2, 'G': 0.3, 'T': 0.3}
E         + {'A': 0.16666666666666666, 'C': 0.16666666666666666, 'G': 0.25, 'T': 0.25}

py2bitTest/test.py:45: AssertionError
========================================================= short test summary info ==========================================================
FAILED py2bitTest/test.py::Test::testBases - AssertionError: assert {'A': 0.16666666666666666, 'C': 0.16666666666666666, 'T': 0.25, 'G': 0.25} == {'A': 0.2, 'C': 0.2, 'T': 0.3, 'G'...
======================================================= 1 failed, 6 passed in 0.26s ========================================================
[deco]~/src/py2bit ❱ git rev-parse HEAD
697884f1c0b0bf4d3c9b82c4fa6a4445a2453c6c