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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 up(self, fileobj_or_path, filename=None, upload_callback=None):
        'Upload a file to current folder and return the new JFSFile'
        close_on_done = False

        if isinstance(fileobj_or_path, six.string_types):
            filename = filename or os.path.basename(fileobj_or_path)
            fileobj_or_path = open(fileobj_or_path, 'rb')
            close_on_done = True
        elif hasattr(fileobj_or_path, 'read'):  # file like
            pass
        else:
            # TODO: handle generators here?
            raise JFSError("Need filename or file-like object")

        if filename is None:
            if hasattr(fileobj_or_path, 'name'):
                filename = os.path.basename(fileobj_or_path.name)
            else:
                raise JFSError("Unable to guess filename")

        log.debug('.up %s ->  %s %s', repr(fileobj_or_path), repr(self.path), repr(filename))
        r = self.jfs.up(posixpath.join(self.path, filename), fileobj_or_path,
            upload_callback=upload_callback)
        if close_on_done:
            fileobj_or_path.close()
        self.sync()
        return r