Update abstract_mixture.py

Author: plidan123

src/mixtures/abstract_mixture.py

@@ -20,6 +20,7 @@ def __init__(self, mixture_form: str, **kwargs: Any) -> None:
             mixture_form: Form of Mixture classical or Canonical
             **kwargs: Parameters of Mixture
         """
+        self.mixture_form=mixture_form
         if mixture_form == "classical":
             self.params = self._params_validation(self._classical_collector, kwargs)
         elif mixture_form == "canonical":