>>> from animalshibrids import composa2noms

>>> composa2noms("gos", "serp")
'goserp'
>>> composa2noms("rata", "serp")
''
>>> composa2noms("miloca", "oca")
''
>>> composa2noms("tortuga", "gat")
'tortugat'
>>> composa2noms("gat", "tortuga")
'gatortuga'
>>> composa2noms("bonobo", "bonobo")
''
>>> composa2noms("estreptococ", "cocodril")
'estreptococodril'