Here's a python function that goes from search string (like "human albumin") and returns a pdb file using @rcsbPDB's top result.

fetch_pdb.py

import requests
import tempfile
def get_pdb(query_string):
    url = "https://search.rcsb.org/rcsbsearch/v1/query"
    query = {
        "query": {
            "type": "terminal",
            "service": "full_text",
            "parameters": {"value": query_string},
        },
        "return_type": "entry",
    }
    r = requests.post(url, json=query)
    if "result_set" in r.json() and len(r.json()["result_set"]) > 0:
        pdbid = r.json()["result_set"][0]["identifier"]
        print('Fetched PDB', pdbid)
        url = f"https://files.rcsb.org/download/{pdbid}.pdb"
        pdb = requests.get(url)
        tmp = tempfile.NamedTemporaryFile(delete=False, suffix=".pdb")
        tmp.write(pdb.text.encode())
        return tmp
    return None