'Returns ``True`` if ``f`` is quadratic in all its variables.
Examples
>>> from sympy import Poly
>>> from sympy.abc import x, y
>>> Poly(x*y + 2, x, y).is_quadratic
True
>>> Poly(x*y**2 + 2, x, y).is_quadratic
False'

@property
def is_quadratic(f):

    return f.rep.is_quadratic
