code: def _base_decoders_for_type(flag_type):
      """Return a list of base decoders for a flag type.
  
      With an explicit flag type, we can provide decoders applicable for
      the type without having to test decoding.
      """
      if flag_type in (None, "auto"):
          return []
      if flag_type in ("string", "path", "existing-path"):
          return [(_string_type, ValueError)]
      if flag_type == "int":
          return [(int, ValueError)]
      if flag_type == "float":
          return [(float, ValueError)]
      if flag_type == "number":
          return _number_decoders()
      if flag_type == "boolean":
          return [(_boolean_type, (ValueError, yaml.YAMLError))]
      log.warning("uknown flag type %s, assuming 'auto'", flag_type)
      return []
  
imports: import logging
  import os
  import re
  import yaml
  from guild import util
  from guild import yaml_util
label_desc: Use image node_id 8 for calling a global function with example usage: _base_decoders_for_type(flag_type) and returns: list, list, list, list, list, _number_decoders, list