Upload a file to LinShare using its rest api.
        The uploaded document uuid will be returned

def upload(self, wg_uuid, file_path, description=None, parent=None):
        """ Upload a file to LinShare using its rest api.
        The uploaded document uuid will be returned"""
        url = "%(base)s/%(wg_uuid)s/nodes" % {
            'base': self.local_base_url,
            'wg_uuid': wg_uuid
        }
        param = {}
        if parent:
            # I use only the last folder uuid, the first ones are not really useful
            if isinstance(parent, (list,)):
                if len(parent) >= 1:
                    parent = parent[-1]
            param['parent'] = parent
        encode = urllib.urlencode(param)
        if encode:
            url += "?"
            url += encode
        return self.core.upload(file_path, url, description)