move versioneer to file

Author: MarcoGorelli

.github/workflows/python-dev.yml

@@ -75,7 +75,6 @@ jobs:
         python -m pip install --upgrade pip setuptools wheel
         python -m pip install -i https://pypi.anaconda.org/scipy-wheels-nightly/simple numpy
         python -m pip install git+https://github.com/nedbat/coveragepy.git
-        python -m pip install versioneer[toml]
         python -m pip install -r ci/deps/actions-311-dev.txt
         python -m pip list
 

ci/deps/actions-311-dev.txt

@@ -6,4 +6,5 @@ pytest-xdist
 pytest-cov
 pytest-asyncio>=0.17
 python-dateutil
-pytz
+pytz
+versioneer[toml]

pandas/_libs/tslibs/offsets.pyx

@@ -367,25 +367,24 @@ cdef class BaseOffset:
     #    dict _cache
 
     def __init__(self, n=1, normalize=False):
-        n = self._validate_n(n)
-        self.n = n
         """
         Number of multiples of the frequency.
 
         Examples
         --------
         >>> pd.offsets.Hour(5).n
         5
-        """
-        self.normalize = normalize
-        """
+
         Return boolean whether the frequency can align with midnight.
 
         Examples
         --------
         >>> pd.offsets.Hour(5).normalize
         False
         """
+        n = self._validate_n(n)
+        self.n = n
+        self.normalize = normalize
         self._cache = {}
 
     def __eq__(self, other) -> bool: