implemented mutiple download feature.

mdrsclient/api/file.py

@@ -80,3 +80,17 @@ class FileApi(BaseApi):
         response = self._get(url)
         self._raise_response_error(response)
         return response.json()
+
+    def download(self, file: File, path: str) -> bool:
+        print(self.__class__.__name__ + "::" + sys._getframe().f_code.co_name)
+        url = self.connection.build_url("v2/", file.download_url)
+        r = self.connection.session.get(url, stream=True)
+        try:
+            with open(path, "wb") as f:
+                for chunk in r.iter_content(chunk_size=4096):
+                    if chunk:
+                        f.write(chunk)
+                        f.flush()
+        except PermissionError:
+            print(f"Cannot create file `{path}`: Permission denied.")
+        return True