parameters: (partitions, directory)
return_statement: return return_dict
docstring: Validate partitions and images.
  
    Validate all partition names and partition directories. Cannot stop mid
    flash so its important to validate everything first.
  
    Args:
      Partitions: partitions to be tested.
      directory: directory containing the images.
  
    Returns:
      Dictionary with exact partition, image name mapping.
docstring_summary: Validate partitions and images.
docstring_tokens: Validate partitions and images .
function: def _FindAndVerifyPartitionsAndImages(partitions, directory):
    """Validate partitions and images.
  
    Validate all partition names and partition directories. Cannot stop mid
    flash so its important to validate everything first.
  
    Args:
      Partitions: partitions to be tested.
      directory: directory containing the images.
  
    Returns:
      Dictionary with exact partition, image name mapping.
    """
  
    files = os.listdir(directory)
    return_dict = collections.OrderedDict()
  
    def find_file(pattern):
      for filename in files:
        if fnmatch.fnmatch(filename, pattern):
          return os.path.join(directory, filename)
      return None
    for partition in partitions:
      partition_info = _KNOWN_PARTITIONS[partition]
      image_file = find_file(partition_info['image'])
      if image_file:
        return_dict[partition] = image_file
      elif not partition_info.get('optional'):
        raise device_errors.FastbootCommandFailedError(
            'Failed to flash device. Could not find image for %s.',
            partition_info['image'])
    return return_dict
function_tokens: def _FindAndVerifyPartitionsAndImages ( partitions , directory ) : files = os . listdir ( directory ) return_dict = collections . OrderedDict ( ) def find_file ( pattern ) : for filename in files : if fnmatch . fnmatch ( filename , pattern ) : return os . path . join ( directory , filename ) return None for partition in partitions : partition_info = _KNOWN_PARTITIONS [ partition ] image_file = find_file ( partition_info [ 'image' ] ) if image_file : return_dict [ partition ] = image_file elif not partition_info . get ( 'optional' ) : raise device_errors . FastbootCommandFailedError ( 'Failed to flash device. Could not find image for %s.' , partition_info [ 'image' ] ) return return_dict