move concat to __init__

Author: MarcoGorelli

spec/API_specification/dataframe_api/__init__.py

@@ -1,6 +1,7 @@
 """
 Function stubs and API documentation for the DataFrame API standard.
 """
+from typing import Sequence
 
 from .column_object import *
 from .dataframe_object import *
@@ -12,3 +13,26 @@
 String representing the version of the DataFrame API specification to which the
 conforming implementation adheres.
 """
+
+def concat(dataframes: Sequence[DataFrame]) -> DataFrame:
+    """
+    Concatenate DataFrames vertically.
+
+    To concatenate horizontally, please use ``insert``.
+
+    Parameters
+    ----------
+    dataframes : Sequence[DataFrame]
+        DataFrames to concatenate.
+        Column names, ordering, and dtypes must match.
+
+    Notes
+    -----
+    The order in which the input DataFrames appear in
+    the output is preserved.
+
+    Returns
+    -------
+    DataFrame
+    """
+    ...

spec/API_specification/dataframe_api/dataframe_object.py

@@ -241,29 +241,6 @@ def get_column_names(self) -> Sequence[str]:
         """
         ...
 
-    def concat(self, other: Sequence[DataFrame]) -> DataFrame:
-        """
-        Concatenate current and other DataFrames vertically.
-
-        To concatenate horizontally, please use ``insert``.
-
-        Parameters
-        ----------
-        other : Sequence[DataFrame]
-            DataFrames to concatenate with.
-            Column names, ordering, and dtypes must match.
-
-        Notes
-        -----
-        The order in which the input DataFrames appear in
-        the output is preserved.
-
-        Returns
-        -------
-        DataFrame
-        """
-        ...
-
     def sorted_indices(
         self,
         keys: Sequence[str],