Switch      : 800215-00-02 0805G-00232 Rev 2.0 BootROM: 1.0.3.1    IMG: 15.3.1.4
PSU         : 700214-00-05 YT675-00893 Rev 2.0 BootROM: 3.0.2.9    IMG: 19.3.6.9

import re
strs = [
  'Switch : 800215-00-02 0805G-00232 Rev 2.0 BootROM: 1.0.3.1 IMG: 15.3.1.4',
  'PSU: : 700214-00-05 YT675-00893 Rev 2.0 BootROM: 3.0.2.9 IMG: 19.3.6.9'
]
regex = '^Switch.+(w{5}-w{5})'
for str in strs:
  result = re.compile(regex).search(str)
  if result is not None:
    print(result.groups(1))