No explicit way to add blank lines to the beginning or end of example or source blocks.

For example: describing HTTP header:

-------------------------------------------------------------------

HTTP header consists of colon-separated name-value pairs,

and terminated by a CRLF character sequence, e.g.:

#+BEGIN_EXAMPLE

GET / HTTP/1.1

Host: www.example.com

#+END_EXAMPLE

This is line break at the end of HTTP header.

-------------------------------------------------------------------

But the blank line at end of example block is not exported, and neither in src block,

I check the source, and found it maybe because of the function `org-split-string',

its description as follow:

(defun org-split-string (string &optional separators)

  "Splits STRING into substrings at SEPARATORS.

No empty strings are returned if there are matches at the beginning

and end of string."

  ...)

It means `org-split-string' will ignore all blank lines at the beginning and the end,

but what if I need some blank lines in the beginning or the end?