sage: s = ZZ.random_element(1,5).abs()
sage: gs = [ R.random_element() for idx in range(s) ]
sage: f = R.random_element(ZZ.random_element(10).abs())
sage: s = ZZ.random_element(1,5).abs()
sage: gs = [ R.random_element() for idx in range(s) ]
sage: f = R.random_element(ZZ.random_element(10).abs())