text: # This file is part of the Blockchain Data Trading Simulator
  #    https://gitlab.com/MatthiasLohr/bdtsim
  #
  # Copyright 2020 Matthias Lohr <mail@mlohr.com>
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #    http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import argparse
  
  from bdtsim.data_provider import DataProviderManager
  from .command_manager import SubCommand
  
  
  class ListDataProvidersSubCommand(SubCommand):
      help = 'print a list of supported data providers'
  
      def __call__(self, args: argparse.Namespace) -> None:
          for name in DataProviderManager.data_providers.keys():
              print(name)
  