org-re-property
org-re-property is a compiled Lisp function in `org.el
'.
(org-re-property PROPERTY &optional LITERAL ALLOW-NULL)
Return a regexp matching a PROPERTY line.
When optional argument LITERAL is non-nil, do not quote PROPERTY.
This is useful when PROPERTY is a regexp. When ALLOW-NULL is
non-nil, match properties even without a value.
Match group 3 is set to the value when it exists. If there is no
value and ALLOW-NULL is non-nil, it is set to the empty string.