after except error how to rerun try in python code example

Example 1: try except python

try:
  print("I will try to print this line of code")
except:
  print("I will print this line of code if an error is encountered")

Example 2: python file open try except error

def FileCheck(fn):
    try:
      open(fn, "r")
      return 1
    except IOError:
      print "Error: File does not appear to exist."
      return 0

result = FileCheck("testfile")
print result