import warnings

__all__ = ['deprecated']

def deprecated(func):
    """This is a decorator which can be used to mark functions
    as deprecated. It will result in a warning being emitted
    when the function is used."""
    def new_func(*args, **kwargs):
        warnings.warn("Call to deprecated function %s." % func.__name__,
                      category=DeprecationWarning, stacklevel=2)
        return func(*args, **kwargs)
    new_func.__name__ = func.__name__
    new_func.__doc__ = func.__doc__
    new_func.__dict__.update(func.__dict__)
    return new_func
