  def PrepareCreateDiskCopyCmd(
      self,
      instance_name: Optional[str] = None,
      disk_name: Optional[str] = None) -> str:
    """Create a disk copy.

    Args:
      instance_name (str): Name of the instance to copy disk from.
      disk_name (str): Name of the disk to copy.

    Returns:
      str: The CLI command to run.
    """
    cmd = 'cloudforensics gcp --project={0:s} copydisk {0:s} {1:s}'.format(
        self.gcp.project_id, self.gcp.default_zone)
    if instance_name:
      cmd += ' --instance_name={0:s}'.format(instance_name)
    elif disk_name:
      cmd += ' --disk_name={0:s}'.format(disk_name)
    logger.info('CLI command: {0:s}'.format(cmd))
    return cmd
Create a disk copy.

Args:
instance_name (str): Name of the instance to copy disk from.
disk_name (str): Name of the disk to copy.

Returns:
str: The CLI command to run.
tests/providers/gcp/gcp_cli.py