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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def image_from_file(filename,
                    remote_addr=None,
                    cert=None,
                    key=None,
                    verify_cert=True,
                    aliases=None,
                    public=False,
                    saltenv='base',
                    _raw=False):
    ''' Create an image from a file

        filename :
            The filename of the rootfs

        remote_addr :
            An URL to a remote Server, you also have to give cert and key if
            you provide remote_addr and its a TCP Address!

            Examples:
                https://myserver.lan:8443
                /var/lib/mysocket.sock

        cert :
            PEM Formatted SSL Certificate.

            Examples:
                ~/.config/lxc/client.crt

        key :
            PEM Formatted SSL Key.

            Examples:
                ~/.config/lxc/client.key

        verify_cert : True
            Wherever to verify the cert, this is by default True
            but in the most cases you want to set it off as LXD
            normaly uses self-signed certificates.

        aliases : []
            List of aliases to append to the copied image

        public : False
            Make this image public available

        saltenv : base
            The saltenv to use for salt:// copies

        _raw : False
            Return the raw pylxd object or a dict of the image?

        CLI Examples:

        ..code-block:: bash

            $ salt '*' lxd.image_from_file salt://lxd/files/busybox.tar.xz aliases=["busybox-amd64"]
    '''
    if aliases is None:
        aliases = []

    cached_file = __salt__['cp.cache_file'](filename, saltenv=saltenv)
    data = b''
    with salt.utils.files.fopen(cached_file, 'r+b') as fp:
        data = fp.read()

    client = pylxd_client_get(remote_addr, cert, key, verify_cert)

    try:
        image = client.images.create(data, public=public, wait=True)
    except pylxd.exceptions.LXDAPIException as e:
        raise CommandExecutionError(six.text_type(e))

    # Aliases support
    for alias in aliases:
        image_alias_add(image, alias)

    if _raw:
        return image

    return _pylxd_model_to_dict(image)