def parse_prefs_file(prefs_string):
 try:
  prefs = dict(eval(prefs_string))
 except TypeError:
  raise QiimeParseError('Invalid prefs file. Prefs file must contain a valid prefs dictionary.')
 return prefs

def parse_prefs_file ( prefs_string ) : try : prefs = dict ( eval ( prefs_string ) ) except TypeError : raise QiimeParseError ( 'Invalid prefs file. Prefs file must contain a valid prefs dictionary.' ) return prefs
returns prefs dict evaluated from prefs_string .