def _uniquely_named_symbol(xname, *exprs):
 prefix = '%s'
 x = (prefix % xname)
 syms = set().union(*[e.free_symbols for e in exprs])
 while any(((x == str(s)) for s in syms)):
  prefix = ('_' + prefix)
  x = (prefix % xname)
 return _symbol(x)

def _uniquely_named_symbol ( xname , * exprs ) : prefix = '%s' x = ( prefix % xname ) syms = set ( ) . union ( * [ e . free_symbols for e in exprs ] ) while any ( ( ( x == str ( s ) ) for s in syms ) ) : prefix = ( '_' + prefix ) x = ( prefix % xname ) return _symbol ( x )
return a symbol which .