The president, peter williamson, had how many home grounds?
{'header': ['Team', 'Head Coach', 'President', 'Home Ground', 'Location', 'Founded', 'Website'], 'page_title': 'Football Gold Coast', 'section_title': 'Premier League', 'caption': 'Premier League', 'rows': [['Burleigh Heads Bulldogs Soccer Club', 'Colin Phelan', 'Steve Kazmer', 'Pizzey Park, Miami', 'Miami', '1983', 'http://www.burleighbulldogs.org/'], ['Merrimac FC', 'Brett Budwee', 'Tony Di Pietro', 'Tony Cecco Field, Clear Island Waters', 'Clear Island Waters', '1978', "http://www.merrimacfootballclub.com.au'''"], ['Gold Coast Knights', 'Steve Radoslavic', 'Mario Volarevic', 'Croatian Sports Centre, Carrara', 'Carrara', '1978', 'http://www.gcknights.com.au/'], ['Broadbeach United', 'Lee Vernon', 'Michael Doyle', 'Chelsea Ave, Broadbeach', 'Broadbeach', '1962', "http://www.broadbeachunited.com.au'''"], ['Palm Beach Sharks Soccer Club', 'Mark Wakeling', 'Peter Williamson', '19th Avenue Stadium, Palm Beach', 'Palm Beach', '1966', 'http://palmbeachfc.com.au/'], ['Mudgeeraba Soccer Club', 'Steve Beever', 'Bryan Williams', 'Sidd Bigg Park, Mudgeeraba', 'Mudgeeraba', '1980', 'http://www.mudgeerabasoccer.com/']]}