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 _testrefastpath(repat):
    """Test if a re pattern can use fast path.

    That is, for every "$A/$B" path the pattern matches, "$A" must also be
    matched,

    Return True if we're sure it is. Return False otherwise.
    """
    # XXX: It's very hard to implement this. These are what need to be
    # supported in production and tests. Very hacky. But we plan to get rid
    # of re matchers eventually.

    # Rules like "(?!experimental/)"
    if repat.startswith("(?!") and repat.endswith(")") and repat.count(")") == 1:
        return True

    # Rules used in doctest
    if repat == "(i|j)$":
        return True

    return False