Seeking a file at a specific byte position or location, usually useful to debug a BiguQuery export error

fileseek.py

import argparse
parser = argparse.ArgumentParser()
parser = argparse.ArgumentParser(description="go to the line of a specific position")
parser.add_argument("input_fname", help = "The input csv file that we will be reading")
parser.add_argument("pos", help="position where we will be seeking the line",  type=float)
args = parser.parse_args()
fname = args.input_fname
position = args.pos
try:
    with open(fname) as file:  # don't you go correcting me on naming it file. we don't call file directly anyway!
        file.seek(position)  # zero in base case
        for line in file:
            position += len(line)
            print(line)
            break
except:
    # yes, a naked exception. TWO faux pas in one answer?!?
    print('exception occurred at position {}'.format(position))
    raise # re-raise to see traceback or what have you