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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 deployments(self) -> Union["Deployments", Dict[None, None]]: """ Returns a ``Deployments`` object containing all the deployment data and contract factories of a ``Package``'s `contract_types`. Automatically filters deployments to only expose those available on the current ``Package.w3`` instance. .. code:: python package.deployments.get_instance("ContractType") """

        if not check_for_deployments(self.manifest):
            return {}

        all_blockchain_uris = self.manifest["deployments"].keys()
        matching_uri = validate_single_matching_uri(all_blockchain_uris, self.w3)

        deployments = self.manifest["deployments"][matching_uri]
        all_contract_factories = {
            deployment_data["contract_type"]: self.get_contract_factory(
                deployment_data["contract_type"]
            )
            for deployment_data in deployments.values()
        }
        validate_deployments_tx_receipt(deployments, self.w3, allow_missing_data=True)
        linked_deployments = get_linked_deployments(deployments)
        if linked_deployments:
            for deployment_data in linked_deployments.values():
                on_chain_bytecode = self.w3.eth.getCode(
                    to_canonical_address(deployment_data["address"])
                )
                unresolved_linked_refs = normalize_linked_references(
                    deployment_data["runtime_bytecode"]["link_dependencies"]
                )
                resolved_linked_refs = tuple(
                    self._resolve_linked_references(link_ref, deployments)
                    for link_ref in unresolved_linked_refs
                )
                for linked_ref in resolved_linked_refs:
                    validate_linked_references(linked_ref, on_chain_bytecode)

        return Deployments(deployments, all_contract_factories, self.w3)