Fix error when empty lines are present before "ATOMIC_POSITIONS" in pw.in input file

[Shibu778]

Description:
This pull request adds a condition to handle empty lines when parsing the pw.in input file. Specifically, the code now checks if a line is not empty before attempting to access its first element, preventing an error when empty lines are encountered before the "ATOMIC_POSITIONS" section.
The updated condition is:

if line.split() and line.split()[0] == "ATOMIC_POSITIONS":

This ensures that the script processes "ATOMIC_POSITIONS" correctly even if there are blank lines in the input, improving robustness and preventing potential crashes during parsing.

[vyu16]

Thanks for reporting this and for the fix! We have replaced this line and the preceding line with

if line.strip().startswith("ATOMIC_POSITIONS"):

The code now works correctly for pw.in with empty lines. This fix will be available in the next release of WEST.

[Shibu778]

Thanks.