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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 mkfs(device, fs_type, **kwargs):
    '''
    Create a file system on the specified device

    CLI Example:

    .. code-block:: bash

        salt '*' extfs.mkfs /dev/sda1 fs_type=ext4 opts='acl,noexec'

    Valid options are:

    * **block_size**: 1024, 2048 or 4096
    * **check**: check for bad blocks
    * **direct**: use direct IO
    * **ext_opts**: extended file system options (comma-separated)
    * **fragment_size**: size of fragments
    * **force**: setting force to True will cause mke2fs to specify the -F
      option twice (it is already set once); this is truly dangerous
    * **blocks_per_group**: number of blocks in a block group
    * **number_of_groups**: ext4 option for a virtual block group
    * **bytes_per_inode**: set the bytes/inode ratio
    * **inode_size**: size of the inode
    * **journal**: set to True to create a journal (default on ext3/4)
    * **journal_opts**: options for the fs journal (comma separated)
    * **blocks_file**: read bad blocks from file
    * **label**: label to apply to the file system
    * **reserved**: percentage of blocks reserved for super-user
    * **last_dir**: last mounted directory
    * **test**: set to True to not actually create the file system (mke2fs -n)
    * **number_of_inodes**: override default number of inodes
    * **creator_os**: override "creator operating system" field
    * **opts**: mount options (comma separated)
    * **revision**: set the filesystem revision (default 1)
    * **super**: write superblock and group descriptors only
    * **fs_type**: set the filesystem type (REQUIRED)
    * **usage_type**: how the filesystem is going to be used
    * **uuid**: set the UUID for the file system

    See the ``mke2fs(8)`` manpage for a more complete description of these
    options.
    '''
    kwarg_map = {'block_size': 'b',
                 'check': 'c',
                 'direct': 'D',
                 'ext_opts': 'E',
                 'fragment_size': 'f',
                 'force': 'F',
                 'blocks_per_group': 'g',
                 'number_of_groups': 'G',
                 'bytes_per_inode': 'i',
                 'inode_size': 'I',
                 'journal': 'j',
                 'journal_opts': 'J',
                 'blocks_file': 'l',
                 'label': 'L',
                 'reserved': 'm',
                 'last_dir': 'M',
                 'test': 'n',
                 'number_of_inodes': 'N',
                 'creator_os': 'o',
                 'opts': 'O',
                 'revision': 'r',
                 'super': 'S',
                 'usage_type': 'T',
                 'uuid': 'U'}

    opts = ''
    for key in kwargs:
        if key in kwarg_map:
            opt = kwarg_map[key]
            if kwargs[key] == 'True':
                opts += '-{0} '.format(opt)
            else:
                opts += '-{0} {1} '.format(opt, kwargs[key])
    cmd = 'mke2fs -F -t {0} {1}{2}'.format(fs_type, opts, device)
    out = __salt__['cmd.run'](cmd, python_shell=False).splitlines()
    ret = []
    for line in out:
        if not line:
            continue
        elif line.startswith('mke2fs'):
            continue
        elif line.startswith('Discarding device blocks'):
            continue
        elif line.startswith('Allocating group tables'):
            continue
        elif line.startswith('Writing inode tables'):
            continue
        elif line.startswith('Creating journal'):
            continue
        elif line.startswith('Writing superblocks'):
            continue
        ret.append(line)
    return ret