pyMaintainCounterOnTextFile

# Student Exercise. Create, Access and Update a counter on a text file

from os.path import getsize

arch = "contador.txt"

def archExist(name):
    try:
        fin = open(name)            # 'rt' is the default mode
        fin.close()
        return True                 # just do the return here, no need for 'else: return True' later
    except FileNotFoundError:
        return False


# Create a text file containing a count of the given value
def crearArch(name, count):         # 'count' is the value to be written to the file
    # I don't see any point in using a "Try:" here.
    # Anything that went wrong would be well beyond your control. Such as "disk full" !!
    fout = open(name, 'w')
    fout.write(str(count))
    fout.close()
    if count == 1:
        print(f"File {name} created OK")
    else:
        print(f"File {name} updated OK. New count is {count}")

def archVacio(none):

    return getsize(none) == 0           # shorthand method. Returns True or False based on the test


if not archExist(arch) or archVacio(arch):
    crearArch(arch, 1)          # create initial 'arch' file with a count of one
else:
    # Again, I see no point in using "Try" here. You have already proved the file exists
    afile = open(arch)
    newctr = int(afile.read()) + 1
    afile.close()
    crearArch(arch, newctr)      # re-create arch file with the latest count