Repository: Zeroto521/my-data-toolkit

Issue:
EHN: let `register_*_method` support alias feature
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- [x] closes #379 and #282
- [x] whatsnew entry

This could use accessor easier, e.g. `Series.lens` -> `Series.len`, `Series.get_attr` -> `Series.getattr`.
Before this PR, `len` is a python keyword, so it can't use `len` as the method name.
This PR will cause v0.0.9 version delay.


Discussion:
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------

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Resolving patch:
diff --git a/dtoolkit/accessor/series.py b/dtoolkit/accessor/series.py
--- a/dtoolkit/accessor/series.py
+++ b/dtoolkit/accessor/series.py
@@ -377,6 +377,7 @@ def lens(s: pd.Series) -> pd.Series:
 
         Call this method via ``Series.lens()`` is deprecated and will be removed
         in **0.0.10**. Please call it via ``Series.len()`` instead.
+        (Warning added DToolKit **0.0.9**)
 
     Return the length of each element in the series.
 


Test patch: