code: def _init_sources(self, data):
      if isinstance(data, list):
          return [
              self._init_resource_source(src_data) for src_data in data
          ]
      raise ResourceFormatError(
          f"invalid sources value for resource '{self.fullname}': {data!r}"
      )
  
imports: import collections
  import copy
  import logging
  import operator
  import pprint
  from guild import util
label_desc: Use image node_id 4 for calling the ResourceDef obj's underlying member method code with example usage: obj._init_sources(data) and returns: unknown