def download_file(url, dest=None, chunk_size=1024, replace="ask",
                  label="Downloading {dest_basename} ({size:.2f}MB)",
                  expected_extension=None):
    """Download a file from a given URL and display progress.

    :param dest: If the destination exists and is a directory, the filename
        will be guessed from the Content-Disposition header. If the destination
        is an existing file, the user will either be prompted to overwrite, or
        the file will be replaced (depending on the value of **replace**). If
        the destination does not exist, it will be used as the filename.
    :param int chunk_size: bytes read in at a time.
    :param replace: If `False`, an existing destination file will not be
        overwritten.
    :param label: a string which is formatted and displayed as the progress bar
        label. Variables provided include *dest_basename*, *dest*, and *size*.
    :param expected_extension: if set, the filename will be sanitized to ensure
        it has the given extension. The extension should not start with a dot
        (`.`).
    """
    dest = Path(dest or url.split("/")[-1])
    response = get(url, stream=True)
    if (dest.exists()
            and dest.is_dir()
            and "Content-Disposition" in response.headers):
        content_disposition = rfc6266.parse_requests_response(response)
        if expected_extension is not None:
            filename = content_disposition.filename_sanitized(
                expected_extension)
        filename = secure_filename(filename)
        dest = dest / filename
    if dest.exists() and not dest.is_dir():
        if (replace is False
                or replace == "ask"
                and not click.confirm("Replace {}?".format(dest))):
            return str(dest)
    size = int(response.headers.get("content-length", 0))
    label = label.format(dest=dest, dest_basename=dest.name,
                         size=size/1024.0/1024)
    with click.open_file(str(dest), "wb") as f:
        content_iter = response.iter_content(chunk_size=chunk_size)
        with click.progressbar(content_iter, length=size/1024,
                               label=label) as bar:
            for chunk in bar:
                if chunk:
                    f.write(chunk)
                    f.flush()
    return str(dest)
def zoneplan(wdg, ax=0):
    """plot zone plan of winding wdg"""
    from matplotlib.patches import Rectangle
    upper, lower = wdg.zoneplan()
    Qb = len([n for l in upper for n in l])
    from femagtools.windings import coil_color
    rh = 0.5
    if lower:
        yl = rh
        ymax = 2*rh + 0.2
    else:
        yl = 0
        ymax = rh + 0.2
    if ax == 0:
        ax = plt.gca()
    ax.axis('off')
    ax.set_xlim([-0.5, Qb-0.5])
    ax.set_ylim([0, ymax])
    ax.set_aspect(Qb/6+0.3)

    for i, p in enumerate(upper):
        for x in p:
            ax.add_patch(Rectangle((abs(x)-1.5, yl), 1, rh,
                                   facecolor=coil_color[i],
                                   edgecolor='white', fill=True))
            s = f'+{i+1}' if x > 0 else f'-{i+1}'
            ax.text(abs(x)-1, yl+rh/2, s, color='black',
                    ha="center", va="center")
    for i, p in enumerate(lower):
        for x in p:
            ax.add_patch(Rectangle((abs(x)-1.5, yl-rh), 1, rh,
                                   facecolor=coil_color[i],
                                   edgecolor='white', fill=True))
            s = f'+{i+1}' if x > 0 else f'-{i+1}'
            ax.text(abs(x)-1, yl-rh/2, s, color='black',
                    ha="center", va="center")

    yu = yl+rh
    step = 1 if Qb < 25 else 2
    if lower:
        yl -= rh
    margin = 0.05
    ax.text(-0.5, yu+margin, f'Q={wdg.Q}, p={wdg.p}, q={round(wdg.q,4)}',
            ha='left', va='bottom', size=15)
    for i in range(0, Qb, step):
        ax.text(i, yl-margin, f'{i+1}', ha="center", va="top")