I noticed a few more functions using ``array_function_dispatch`` where I had
not set the module, using this script::

    import types

    def check_module(module):
        for name in dir(module):
            item = getattr(module, name)
            if isinstance(item, types.FunctionType):
                print(f'{item.__module__}.{item.__name__}')

    >>> import numpy
    >>> check_module(numpy)
    ...

Note that functions without overrides like ``numpy.ones`` still display the
module in which they are defined, e.g., ``numpy.core.numeric.ones``. We should
probably fix that, too, probably most cleanly adding a decorator that sets
``__module__``, e.g.,

    def set_module(module):
        def decorator(func):
            func.__module__ = module
            return func
        return decorator

    ...

    @set_module('numpy')
    def ones(shape, dtype=None, order='C'):
        ...