class_docstr: A class for representing multivariate polynomial rings. 
docstr: Convert SymPy's expression to `dtype`. 
docstr_tok: ["Convert","SymPy","'s","expression","to","`","dtype","`","."]
code: def from_sympy(self, a):
      """Convert SymPy's expression to `dtype`."""
      return self.ring.from_expr(a)
  
imports: from sympy.polys.domains.ring import Ring
  from sympy.polys.domains.compositedomain import CompositeDomain
  from sympy.polys.polyerrors import CoercionFailed, GeneratorsError
  from sympy.utilities import public
label_desc: Use image node_id 12 for calling the PolynomialRing obj's underlying member method code with example usage: obj.from_sympy(a) and returns: self