Let's say I have files
bla_foo.txt
bla_Foo.txt
bla_bar.txt
xyz_Bar.txt
foo_bla.txt
is it possible to specify several patterns with glob? 
For example how can I select only *Foo.txt, *foo.txt, *bar.txt and *Bar.txt?
I know how to select only *Foo.txt and *foo.txt with glob('*[Ff]oo.txt'). But what if *bar.txt and *Bar.txt are also acceptable? Is this even possible with glob or will I have to create two globs
glob('*[Ff]oo.txt')
glob('*[Bb]ar.txt')