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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 get_structures(self, primitive=True):
 """ Return list of structures in CIF file. primitive boolean sets whether a conventional cell structure or primitive cell structure is returned. Args: primitive (bool):
 Set to False to return conventional unit cells. Defaults to True. With magnetic CIF files, will return primitive magnetic cell which may be larger than nuclear primitive cell. Returns: List of Structures. """

        structures = []
        for d in self._cif.data.values():
            try:
                s = self._get_structure(d, primitive)
                if s:
                    structures.append(s)
            except (KeyError, ValueError) as exc:
                # Warn the user (Errors should never pass silently)
                # A user reported a problem with cif files produced by Avogadro
                # in which the atomic coordinates are in Cartesian coords.
                self.errors.append(str(exc))
                warnings.warn(str(exc))
        if self.errors:
            warnings.warn("Issues encountered while parsing CIF:")
            for error in self.errors:
                warnings.warn(error)
        if len(structures) == 0:
            raise ValueError("Invalid cif file with no structures!")
        return structures