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pandas-snippets.md

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+- [Basics](#basics)
+
+# Basics
+
+```python
+df.loc[:, "D"] = np.array([5] * len(df))
+df.loc[:, ["A", "B"]]
+df.sort_index(axis=1, ascending=False) #axis=1 sort columns by labels, axis=0 sort by index
+```