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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def as_dict(self, verbosity=0):
 """ Json-serializable dict representation of PeriodicSite. Args: verbosity (int):
 Verbosity level. Default of 0 only includes the matrix representation. Set to 1 for more details such as cartesian coordinates, etc. """

        species_list = []
        for spec, occu in self._species.items():
            d = spec.as_dict()
            del d["@module"]
            del d["@class"]
            d["occu"] = occu
            species_list.append(d)

        d = {"species": species_list,
             "abc": [float(c) for c in self._frac_coords],
             "lattice": self._lattice.as_dict(verbosity=verbosity),
             "@module": self.__class__.__module__,
             "@class": self.__class__.__name__}

        if verbosity > 0:
            d["xyz"] = [float(c) for c in self.coords]
            d["label"] = self.species_string

        d["properties"] = self.properties
        return d