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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 avail_images(call=None):
    '''
    Return available Linode images.

    CLI Example:

    .. code-block:: bash

        salt-cloud --list-images my-linode-config
        salt-cloud -f avail_images my-linode-config
    '''
    if call == 'action':
        raise SaltCloudException(
            'The avail_images function must be called with -f or --function.'
        )

    response = _query('avail', 'distributions')

    ret = {}
    for item in response['DATA']:
        name = item['LABEL']
        ret[name] = item

    return ret