For python 2.7: pip install glob2

For python 3.7: pip3 install glob2

I tried with different Scenarios,and finally got exact solution which satisfies all my conditions. First I'm checking for user input file is available or not in the specified directory, If it is available then globing all files with same file with (_) all at the end appending match file to same list.

If user input if not file is not available in the specified directory then I'm checking for the files with (_) symbol then globing all files into list. At the end iterating through list and got final result.

Program-

from glob import glob
import os
import sys

file_pattern = ''
files_list = list()

arguments = {'ABC', 'PQR', 'XYZ'}

#checking for user provided argument or not
if len(sys.argv[1:2]) is 1:
   file_pattern = str(sys.argv[1:2])
else:   
   print 'run as < python test.py <LineName> >'
   sys.exit(1)
#replace all unnecessary stuff with ('')
file_pattern = file_pattern.replace('[','').replace(']','').replace('\'','')

#checking for line number is provided or not
if file_pattern in arguments:
   print '<Provide LineName with some Number>'
   sys.exit(1)

flag = True
#list of all files containing specified directory
files = os.listdir('<directory name>')

for file_name in files:
   if str(file_name) == str(file_pattern)+'.csv':
      files_list = glob(os.path.join('<directory name>', str(file_pattern)+'_*.csv'))
      #appending match file also to resultant list
      files_list.append('<directory name>'+file_name)
      flag = False
#if specified file is not present in dir check for filename with (_)
if flag:
   files_list = glob(os.path.join('<directory name>', str(file_pattern)+'_*.csv'))

#checking for list contains items or not
if files_list:
   for a_file in sorted(files_list):
      print a_file
else:
   print 'No Such File --> ' + str(file_pattern)+ '\t  <Provide appropriate Name1>'
   sys.exit(1)

Consider directory contains ABC1.csv, ABC1_1.csv, ABC1_2.csv, ABC11.csv, ABC11_1.csv, ABC11_3.csv, ABC11_2.csv files.

Output Scenario :

#if input is ABC1
.\\ABC1.csv
.\\ABC1_1.csv
.\\ABC1_2.csv
#if input is ABC11
.\\ABC11.csv
.\\ABC11_1.csv
.\\ABC11_2.csv
.\\ABC11_3.csv