1 | initial version |
First of all, do you really need to? Just allow any input, if it does not have the methods you are calling then you will get a suitable AttributeError
exception thrown. AKA duck-typing.
If you are sure that you actually have to check the type, use the convenience functions:
sage: from sage.rings.polynomial.polynomial_ring import is_PolynomialRing
sage: is_PolynomialRing('string')
False
sage: from sage.rings.polynomial.multi_polynomial_ring import is_MPolynomialRing
sage: is_MPolynomialRing('string')
False