docs: Fix return annotation in API docstrings (#253)

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Fixes internal issue 314367409 🦕

Author: shobsi

third_party/bigframes_vendored/pandas/core/frame.py

@@ -226,7 +226,7 @@ def from_dict(
                 if used with ``orient='columns'`` or ``orient='tight'``.
 
         Returns:
-            DataFrame
+            DataFrame: DataFrame.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -267,7 +267,7 @@ def from_records(
                 Number of rows to read if data is an iterator.
 
         Returns:
-            DataFrame
+            DataFrame: DataFrame.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -717,7 +717,7 @@ def to_markdown(
                 These parameters will be passed to `tabulate <https://pypi.org/project/tabulate>`_.
 
         Returns:
-            DataFrame in Markdown-friendly format.
+            DataFrame: DataFrame in Markdown-friendly format.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1272,7 +1272,7 @@ def sort_values(
              if `first`; `last` puts NaNs at the end.
 
         Returns:
-            DataFrame with sorted values.
+            DataFrame: DataFrame with sorted values.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1282,7 +1282,7 @@ def sort_index(
         """Sort object by labels (along an axis).
 
         Returns:
-            The original DataFrame sorted by the labels.
+            DataFrame: The original DataFrame sorted by the labels.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1330,7 +1330,7 @@ def eq(self, other, axis: str | int = "columns") -> DataFrame:
                 (1 or 'columns').
 
         Returns:
-            Result of the comparison.
+            DataFrame: Result of the comparison.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1861,7 +1861,7 @@ def rtruediv(self, other, axis: str | int = "columns") -> DataFrame:
                 (1 or 'columns'). For Series input, axis to match Series index on.
 
         Returns:
-            DataFrame result of the arithmetic operation.
+            DataFrame: DataFrame result of the arithmetic operation.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -2796,7 +2796,7 @@ def any(self, *, axis=0, bool_only: bool = False):
                 Include only boolean columns.
 
         Returns:
-            Series
+            bigframes.series.Series: Series indicating if any element is True per column.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -2843,7 +2843,7 @@ def all(self, axis=0, *, bool_only: bool = False):
                 Include only boolean columns.
 
         Returns:
-            bigframes.series.Series: Series if all elements are True.
+            bigframes.series.Series: Series indicating if all elements are True per column.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -3184,7 +3184,7 @@ def skew(self, *, numeric_only: bool = False):
                 Include only float, int, boolean columns.
 
         Returns:
-            Series
+            Series: Series.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -3225,7 +3225,7 @@ def kurt(self, *, numeric_only: bool = False):
                 Include only float, int, boolean columns.
 
         Returns:
-            Series
+            Series: Series.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -3770,7 +3770,7 @@ def pivot(self, *, columns, index=None, values=None):
                 have hierarchically indexed columns.
 
         Returns:
-            Returns reshaped DataFrame.
+            DataFrame: Returns reshaped DataFrame.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -3808,7 +3808,7 @@ def unstack(self):
         (the analogue of stack when the columns are not a MultiIndex).
 
         Returns:
-            DataFrame or Series
+            DataFrame or Series: DataFrame or Series.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -3866,7 +3866,7 @@ def index(self):
                 dtype=object)
 
         Returns:
-            The index labels of the DataFrame.
+            Index: The index object of the DataFrame.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -4115,7 +4115,7 @@ def dot(self, other):
                 The other object to compute the matrix product with.
 
         Returns:
-            Series or DataFrame
+            Series or DataFrame:
                 If `other` is a Series, return the matrix product between self and
                 other as a Series. If other is a DataFrame, return
                 the matrix product of self and other in a DataFrame.

third_party/bigframes_vendored/pandas/core/series.py

@@ -90,7 +90,7 @@ def index(self):
                 dtype=object)
 
         Returns:
-            The index labels of the Series.
+            Index: The index object of the Series.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -138,7 +138,7 @@ def transpose(self) -> Series:
         Return the transpose, which is by definition self.
 
         Returns:
-            Series
+            Series: Series.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -593,7 +593,7 @@ def corr(self, other, method="pearson", min_periods=None) -> float:
                 are not yet supported, so a result will be returned for at least two observations.
 
         Returns:
-            float;  Will return NaN if there are fewer than two numeric pairs, either series has a
+            float:  Will return NaN if there are fewer than two numeric pairs, either series has a
                 variance or covariance of zero, or any input value is infinite.
         """
         raise NotImplementedError("abstract method")
@@ -611,7 +611,7 @@ def diff(self) -> Series:
                 values.
 
         Returns:
-            {klass}: First differences of the Series.
+            Series: First differences of the Series.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1317,7 +1317,7 @@ def le(self, other) -> Series:
             other: Series, or scalar value
 
         Returns:
-            bigframes.series.Series. The result of the comparison.
+            bigframes.series.Series: The result of the comparison.
 
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
@@ -1331,7 +1331,7 @@ def lt(self, other) -> Series:
         Args:
              other (Series, or scalar value):
 
-         Returns:
+        Returns:
             bigframes.series.Series: The result of the operation.
 
         """
@@ -1588,7 +1588,7 @@ def divmod(self, other) -> Series:
             other: Series, or scalar value
 
         Returns:
-            2-Tuple of Series. The result of the operation. The result is always
+            2-Tuple of Series: The result of the operation. The result is always
             consistent with (floordiv, mod) (though pandas may not).
 
         """
@@ -1603,7 +1603,7 @@ def rdivmod(self, other) -> Series:
             other: Series, or scalar value
 
         Returns:
-            2-Tuple of Series. The result of the operation. The result is always
+            2-Tuple of Series: The result of the operation. The result is always
             consistent with (rfloordiv, rmod) (though pandas may not).
 
         """
@@ -1650,7 +1650,7 @@ def max(
 
 
         Returns:
-            scalar or scalar
+            scalar: Scalar.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1664,7 +1664,7 @@ def min(
         of the ``numpy.ndarray`` method ``argmin``.
 
         Returns:
-            scalar or scalar
+            scalar: Scalar.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1692,7 +1692,7 @@ def var(
         Normalized by N-1 by default.
 
         Returns:
-            scalar or Series (if level specified)
+            scalar or Series (if level specified): Variance.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1702,15 +1702,15 @@ def sum(self):
         This is equivalent to the method ``numpy.sum``.
 
         Returns:
-            scalar
+            scalar: Scalar.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
     def mean(self):
         """Return the mean of the values over the requested axis.
 
         Returns:
-            scalar
+            scalar: Scalar.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1723,15 +1723,15 @@ def median(self, *, exact: bool = False):
                 one. Note: ``exact=True`` not yet supported.
 
         Returns:
-            scalar
+            scalar: Scalar.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
     def prod(self):
         """Return the product of the values over the requested axis.
 
         Returns:
-            scalar
+            scalar: Scalar.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1741,7 +1741,7 @@ def skew(self):
         Normalized by N-1.
 
         Returns:
-            scalar
+            scalar: Scalar.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -1932,7 +1932,7 @@ def clip(self):
                 Maximum threshold value. All values above this threshold will be set to it. A missing threshold (e.g NA) will not clip the value.
 
         Returns:
-            Series.
+            Series: Series.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -2083,7 +2083,7 @@ def is_monotonic_increasing(self) -> bool:
         Return boolean if values in the object are monotonically increasing.
 
         Returns:
-            bool
+            bool: Boolean.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
@@ -2093,7 +2093,7 @@ def is_monotonic_decreasing(self) -> bool:
         Return boolean if values in the object are monotonically decreasing.
 
         Returns:
-            bool
+            bool: Boolean.
         """
         raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)