@Contract("null -> null")
  @Nullable
  private static PsiExpression getReturnExpression(@Nullable PsiStatement block) {
    if (block == null) return null;
    PsiStatement statement = ControlFlowUtils.stripBraces(block);
    PsiReturnStatement returnStatement = tryCast(statement, PsiReturnStatement.class);
    if (returnStatement == null) return null;
    return returnStatement.getReturnValue();
  }
@Contract("null -> null")
  @Nullable
  private static PsiExpression getReturnExpression(@Nullable PsiStatement block)