rded unchanged.

    Examples
    --------
    The following deprecates 'cols', using 'columns' instead

    >>> @deprecate_kwarg(old_arg_name='cols', new_arg_name='columns')
    ... def f(columns=''):
    ...     print(columns)
    ...
    >>> f(columns='should work ok')
    should work ok

    >>> f(cols='should raise warning')  # doctest: +SKIP
    FutureWarning: cols is deprecated, use columns instead
      warnings.warn(msg, FutureWarning)
    should raise warning

    >>> f(cols='should error', columns="can't pass do both")  # doctest: +SKIP
    TypeError: Can only specify 'cols' or 'columns', not both

    >>> @deprecate_kwarg('old', 'new', {'yes': True, 'no': False})
    ... def f(new=False):
    ...     print('yes!' if new else 'no!')
    ...
    >>> f(old='yes')  # doctest: +SKIP
    FutureWarning: old='yes' is deprecated, use new=True instead
      warnings.warn(msg, FutureWarning)
    yes!

    To raise a warning that a keyword will be removed entirely in the future

    >>> @deprecate_kwarg(old_arg_name='cols', new_arg_name=None)
    ... def f(cols='', another_param=''):
    ...     print(cols)
    ...
    >>> f(cols='should raise warning')  # doctest: +SKIP
    FutureWarning: the 'cols' keyword is deprecated and will be removed in a
    future version please takes steps to stop use of 'cols'
    should raise warning
    >>> f(another_param='should not raise warning')  # doctest: +SKIP
    should not raise warning

    >>> f(cols='should raise warning', another_param='')  # doctest: +SKIP
    FutureWarning: the 'cols' keyword is deprecated and will be removed in a
    future version please takes steps to stop use of 'cols'
    should raise warning
    NÚ