code: def upload(self, filename, location=''):
          
          current_folder = self._ftp.pwd()
          self.mkdir(location)
          self.cd(location)
          fl = open(filename, 'rb')
          filename = filename.split('/')[-1]
          self._ftp.storbinary('STOR %s' % filename, fl)
          fl.close()
          self.cd(current_folder)
docs: Uploads a file on the server to the desired location
  
          :param filename: the name of the file to be uploaded.
          :type filename: string
          :param location: the directory in which the file will
                           be stored.
          :type location: string