Run gethead on a FITS image for a single keyword. If a card with this keyword is not found, then the value "None" is returned.

% gethead_1card 
Usage: gethead_1card a.fits NUMWCS 
arg1 - Name of FITS images
arg2 - keyword of desired card

% gethead_1card Rsco3212.fits OBJECT  
N7479

% gethead_1card Rsco3212.fits boodle  
None