def get(url, session=None, silent=not debug, **kwargs):
    """Retrieve a given URL and log response.

    :param session: a :class:`requests.Session` object.
    :param silent: if **True**, response status and URL will not be printed.
    """
    session = session or requests
    kwargs["verify"] = kwargs.get("verify", True)
    r = session.get(url, **kwargs)
    if not silent:
        status_code = click.style(
            str(r.status_code),
            fg="green" if r.status_code in (200, 304) else "red")
        click.echo(status_code + " " + url)
        if r.status_code == 404:
            raise PackageNotFoundError
    return r
def nonlinear_1d(module, grad_input, grad_output):
    delta_out = module.y[: int(module.y.shape[0] / 2)] - module.y[int(module.y.shape[0] / 2):]

    delta_in = module.x[: int(module.x.shape[0] / 2)] - module.x[int(module.x.shape[0] / 2):]
    dup0 = [2] + [1 for i in delta_in.shape[1:]]
    # handles numerical instabilities where delta_in is very small by
    # just taking the gradient in those cases
    grads = [None for _ in grad_input]
    grads[0] = torch.where(torch.abs(delta_in.repeat(dup0)) < 1e-6, grad_input[0],
                           grad_output[0] * (delta_out / delta_in).repeat(dup0))
    return tuple(grads)