CreateTempWithContents - create a temp file with the filename pattern and contents specified.

FileExists checks if a file exists and is not a directory before we try using it to prevent further errors.

FileOrDirectoryExists - check if specified filename (which is a file or directory) exists.

IsDirectory - check if specified filename is a directory.

ReadFile - read the contents of a file and optionally trim any whitespace.

ReadFileAsString - read the contents of a file and optionally trim any whitespace.