Backport r54763: repair missing spaces after \UNIX.
diff --git a/Doc/api/init.tex b/Doc/api/init.tex
index e380bdb..76fcf61 100644
--- a/Doc/api/init.tex
+++ b/Doc/api/init.tex
@@ -245,7 +245,7 @@
program name (set by \cfunction{Py_SetProgramName()} above) and some
environment variables. The returned string consists of a series of
directory names separated by a platform dependent delimiter
- character. The delimiter character is \character{:} on \UNIX and Mac OS X,
+ character. The delimiter character is \character{:} on \UNIX{} and Mac OS X,
\character{;} on Windows. The returned string points into
static storage; the caller should not modify its value. The value
is available to Python code as the list