Fix missing docstring.

Author: NeilGirdhar

src/array_api_extra/_delegation.py

@@ -135,6 +135,9 @@ def one_hot(
         An array with integral dtype having shape ``batch_dims``.
     num_classes : int
         Number of classes in the one-hot dimension.
+    dtype : DType, optional
+        The dtype of the return value.  Defaults to the default float dtype (usually
+        float64).
     axis : int or tuple of ints, optional
         Position(s) in the expanded axes where the new axis is placed.
     xp : array_namespace, optional
@@ -146,7 +149,6 @@ def one_hot(
         An array having the same shape as `x` except for a new axis at the position
         given by `axis` having size `num_classes`.
 
-        The dtype of the return value is the default float dtype (usually float64).
 
         If ``x < 0`` or ``x >= num_classes``, then the result is undefined, may raise
         an exception, or may even cause a bad state.  `x` is not checked.

src/array_api_extra/_lib/_funcs.py

@@ -389,6 +389,7 @@ def one_hot(
     dtype: DType,
     xp: ModuleType,
 ) -> Array:
+    """Helper for _delegation.one_hot."""
     out = xp.zeros((x.size, num_classes), dtype=dtype)
     x_flattened = xp.reshape(x, (-1,))
     if is_numpy_namespace(xp):