title: ''Ticker'' in list comprehension
body: <p>I'm trying to understand this section of the code in which "ticker" gets used in a list comprehension. Can anyone tell me what "ticker" means and where it came from. I'll include the imported modules/libraries for reference. </p>
  
  <pre><code>import itertools
  import pandas as pd
  import pickle
  import os.path
  import xlrd
  import xlwings as xw
  from tkinter import *
  from tkinter.filedialog import askopenfilename
  import re 
  import datetime
      .
      .
      .
  colC = ['' if x is None else x for x in colC]
  colC = [ticker.replace(' USD', '').replace(' SWAP', '').replace(' CVR', 
  '').replace('.USD', '') for ticker in colC]
  colC = [ticker.split()[0] + " Options" if p.match(ticker) else ticker for 
  ticker in colC]
  </code></pre>
  
  <p>Any help is appreciated.</p>