>>> from interchange import interchange
>>> interchange('Today')
'oTady'
>>> interchange('Tomorrow')
'oTomrrwo'
>>> interchange('123456789')
'214365879'
>>> interchange('1234567890')
'2143658709'
>>> interchange('Houston, we have a problem.')
'oHsuot,nw  eaheva p orlbme.'
>>> interchange('A')
'A'