CalculateNetworkRates calculates the download and upload rates for the active network interface.

Cexec executes a command in the default shell and captures the standard output (stdout) and errors (stderr).

GetActiveInterface returns the name of the active network interface.

GetNetworkStats reads the network statistics from /proc/net/dev and returns a map of interface names to their received and transmitted bytes.

PassInts converts a list of strings into integers.