add isfile method

from installsystems.tarball import Tarball

def md5sum(path=None, fileobj=None):

    '''Compute md5 of a file'''

    '''

    Compute md5 of a file

    '''

    if path is None and fileobj is None:

        raise ValueError("No path or fileobj specified")

    if fileobj is None:

    return m.hexdigest()

def copyfileobj(sfile, dfile):

    """Copy data from sfile to dfile coputing length and md5 on the fly"""

    '''

    Copy data from sfile to dfile coputing length and md5 on the fly

    '''

    f_sum = hashlib.md5()

    f_len = 0

    while True:

    return (f_len , f_sum.hexdigest())

def copy(source, destination, uid=None, gid=None, mode=None, timeout=None):

    '''Copy a source to destination. Take care of path type'''

    '''

    Copy a source to destination. Take care of path type

    '''

    stype = pathtype(source)

    dtype = pathtype(destination)

    # ensure destination is not a directory

        chrights(destination, uid, gid, mode)

def mkdir(path, uid=None, gid=None, mode=None):

    '''Create a directory and set rights'''

    '''

    Create a directory and set rights

    '''

    os.mkdir(path)

    chrights(path, uid, gid, mode)

def chrights(path, uid=None, gid=None, mode=None, mtime=None):

    '''Set rights on a file'''

    '''

    Set rights on a file

    '''

    if uid is not None:

        os.chown(path, uid, -1)

    if gid is not None:

        os.utime(path, (mtime, mtime))

def pathtype(path):

    '''Return path type. This is usefull to know what kind of path is given'''

    '''

    Return path type. This is usefull to know what kind of path is given

    '''

    if path.startswith("http://") or path.startswith("https://"):

        return "http"

    if path.startswith("ftp://") or path.startswith("ftps://"):

    else:

        return "file"

def isfile(path):

    '''

    Return True if path is of type file

    '''

    return pathtype(path) == "file"

def abspath(path):

    '''Format a path to be absolute'''

    '''

    Format a path to be absolute

    '''

    ptype = pathtype(path)

    if ptype in ("http", "ssh"):

        return path

        return None

def uopen(path, mode="rb"):

    '''Universal Open

    '''

    Universal Open

    Create a file-like object to a file which can be remote

    '''

    ftype = pathtype(path)

        raise NotImplementedError

def getsize(path):

    '''Get size of a path. Recurse if directory'''

    '''

    Get size of a path. Recurse if directory

    '''

    total_sz = os.path.getsize(path)

    if os.path.isdir(path):

        for root, dirs, files in os.walk(path):