text: In order to do that, we can initialize it directly.store = PGVector(    collection_name=COLLECTION_NAME,    connection_string=CONNECTION_STRING,    embedding_function=embeddings,)Add documentsâ€‹We can add documents to the existing vectorstore.store.add_documents([Document(page_content="foo")])    ['048c2e14-1cf3-11ee-8777-e65801318980']docs_with_score = db.similarity_search_with_score("foo")docs_with_score[0]    (Document(page_content='foo', metadata={}), 3.3203430005457335e-09)docs_with_score[1]    (Document(page_content='A former top litigator in private practice. A former federal public defender. And from a family of public school educators and police officers. A consensus builder. Since sheâ€™s been nominated, sheâ€™s received a broad range of supportâ€”from the Fraternal Order of Police to former judges appointed by Democrats and Republicans. \n\nAnd if we are to advance liberty and justice, we need to secure the Border and fix the immigration system. \n\nWe can do both. At our border, weâ€™ve installed new technology like cutting-edge scanners to better detect drug smuggling.  \n\nWeâ€™ve set up joint patrols with Mexico and Guatemala to catch more human traffickers.  \n\nWeâ€™re putting in place dedicated immigration judges so families fleeing persecution and violence can have their cases heard faster. \n\nWeâ€™re securing commitments and supporting partners in South and Central America to host more refugees and secure their own borders.', metadata={'source': '../../../state_of_the_union.txt'}),     0.2404395365581814)Overriding a vectorstoreâ€‹If you have an existing collection, you override