subroutine hello (a)
 
integer a
 
  write(*,*)'Hello from Fortran90!!!',a
 
end subroutine hello

f2py -m foo -c foo.f90 

$ python
Python 2.7.6 (default, Jun 22 2015, 17:58:13) 
[GCC 4.8.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
> import foo
> foo.hello(15)
 Hello from Fortran90!!!     15

integer[ | *1 | *2 | *4 | *8 ], logical[ | *1 | *2 | *4 | *8 ]
integer*([ -1 | -2 | -4 | -8 ])
character[ | *(*) | *1 | *2 | *3 | ... ]
real[ | *4 | *8 | *16 ], double precision
complex[ | *8 | *16 | *32 ]
<dim> | <start>:<end> | * | :
intent([ in | inout | out | hide | in,out | inout,out | c |
     copy | cache | callback | inplace | aux ])
dimension(<dimspec>)
common, parameter
allocatable
optional, required, external
depend([<names>])
check([<C-booleanexpr>])
note(<LaTeX text>)
usercode, callstatement, callprotoargument, threadsafe, fortranname
pymethoddef
entry