[Python] How to safely check whether a Fortran file exists when reading it with Python?

I need to read in Python a file written in Fortran. To do this, I'm using numpy's f2py. Basically, I write a parse.f90 file:

subroutine read_params(filename, params)
implicit none
! Argument Declarations !
character(len=*), intent(in) :: filename
integer, dimension(4), intent(out) :: params
! Variable Declarations
integer :: i

open (unit=1,status="unknown",file=filename,form="unformatted")
rewind 1
read(1) (params(i), i=1, 4)

end subroutine read_params


Then I compile it with

python -m numpy.f2py -c -m parse parse.f90


And now I can import it in my Python script:

from pathlib import Path
import numpy as np
from .parse import read_params

def do_stuff_with_params(path: Path):
params = read_params(path)
# do something with the parameters
return


Now, my issue is that sometimes the Fortran file may not exist, for example because the user of do_stuff_with_params passed it the wrong path. Since however path is not a Python file object, the usual with open trick doesn't apply. So far, I used the following workaround:

def do_stuff_with_params(path: Path):
if not path.exists():
raise FileNotFoundError(f'{path} does not exist ')
params = read_params(path)
# do something with the parameters
return


But this isn't ideal for the usual reasons (the file may be moved or deleted between the if check and when it's actually opened). Also, I actually need to read the file twice because of Fortran limitations (long story...), so I would have to add two if statements. How can I solve this? I was wondering if I could raise an exception in parse.f90 and pass it to the Python interpreter, but I don't know how to do it.

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