List of best mirrors for IP address 3.143.237.203, located in an unknown country.
I am very sorry, but no mirror was found. Feel free to download directly:
http://mirrordirector-mb.raspbian.org/multiarch/pool/main/l/llvm-toolchain-10/libc++1-10-dbgsym_10.0.1-8+rpi1_arm64.deb