diff --git a/shop_calculator.py b/shop_calculator.py
index e5f8b37..77fcfd9 100644
--- a/shop_calculator.py
+++ b/shop_calculator.py
@@ -1,3 +1,7 @@
+"""
+Morawaliyadda M.G.H.S.M
+EG/2020/4078
+"""
 import csv
 
 discnts = {}
@@ -6,38 +10,62 @@
 curr_rates = {}
 invntry = {}
 
+
 def ld_discnts(file):
+    """
+    Function of ID discnt
+
+    """
     with open(file) as dscnt_file:
-        r = csv.reader(dscnt_file)
-        for rw in r:
-            discnts[rw[0].upper()] = float(rw[1])
+        _reader = csv.reader(dscnt_file)
+        for _rw in _reader:
+            discnts[_rw[0].upper()] = float(_rw[1])
 
 def ld_taxes(file):
+    """
+    Function of ID taxes
+
+    """
     with open(file) as tax_file:
-        r = csv.reader(tax_file)
-        for rw in r:
+        _reader = csv.reader(tax_file)
+        for rw in _reader:
             taxes[rw[0].upper()] = float(rw[1])
 
 def ld_prmtns(file):
+    """
+    Function of ID prmtns
+
+    """
     with open(file) as prmtn_file:
-        r = csv.reader(prmtn_file)
-        for rw in r:
+        _reader = csv.reader(prmtn_file)
+        for rw in _reader:
             prmtns[rw[0]] = float(rw[1])
 
 def ld_curr_rates(file):
+    """
+    Function of ld_curr_rates
+
+    """
     with open(file) as currency_file:
-        r = csv.reader(currency_file)
-        for rw in r:
+        _reader = csv.reader(currency_file)
+        for rw in _reader:
             curr_rates[rw[0].upper()] = float(rw[1])
 
 def ld_invntry(file):
+    """
+    Function of ld_invntry
+
+    """
     with open(file) as inv_file:
-        r = csv.reader(inv_file)
-        for rw in r:
+        _reader = csv.reader(inv_file)
+        for rw in _reader:
             invntry[rw[0].upper()] = int(rw[1])
 
 def main():
+    """
+    main function
 
+    """
     ld_discnts('data/discounts.csv')
     ld_taxes('data/tax_rates.csv')
     ld_prmtns('data/promotions.csv')
@@ -61,11 +89,11 @@ def main():
         if promo:
             qty = qty - (qty // promo)
         dscnt = discnts.get(itm, 0)
-        price = 1.0  
+        price = 1.0       
         dscntd_price = price - (price * dscnt)
         item_price = dscntd_price * qty
         total_price_usd += item_price
-        invntry[itm] -= qty 
+        invntry[itm] -= qty
 
     available_states = list(taxes.keys())
     print("Enter your state. Available states are: ", ', '.join(available_states))
@@ -87,7 +115,9 @@ def main():
     print(f"Total: USD {final_price_usd:.2f}")
 
     available_currencies = list(curr_rates.keys())
-    selected_currency = input("Select currency for payment ({}): ".format(', '.join(available_currencies)))
+    selected_currency = input(
+        "Select currency for payment ({}): ".format(', '.join(available_currencies))
+        )
 
     final_price_currency = final_price_usd * curr_rates.get(selected_currency)
 
diff --git a/travel_cost_calculator.py b/travel_cost_calculator.py
index 27a3d62..b805171 100644
--- a/travel_cost_calculator.py
+++ b/travel_cost_calculator.py
@@ -1,49 +1,69 @@
+"""
+Morawaliyadda M.G.H.S.M
+EG/2020/4078
+"""
 from csv import *
 
 a = {}
 b = {}
 c = {}
 
-def lhr(file):  
-    with open(file) as h:
-        r = reader(h)
-        for row in r:
+def lhr(file): 
+    """
+    Function of Ihr
+
+    """
+    with open(file) as _hours:
+        _reader = reader(_hours)
+        for row in _reader:
             a[row[0]] = float(row[1])
 
 def ler(file): 
+    """
+    Function of ler
+
+    """
     with open(file) as e:
-        r = reader(e)
-        for row in r:
+        _reader = reader(e)
+        for row in _reader:
             b[row[0].upper()] = float(row[1]) * 1 
 
 def lfr(file):
+    """
+    Function of lfr
+
+    """
     with open(file) as f:
-        r = reader(f)
-        for row in r:
+        _reader = reader(f)
+        for row in _reader:
             c[row[0]] = float(row[1])
 
 def main():
+    """
+    Main Function 
+
+    """
     lhr('data/hotel_rates.csv')
     ler('data/exchange_rates.csv')
     lfr('data/flight_costs.csv')
 
-    d = input("Enter your destination: ").upper()
+    _days = input("Enter your destination: ").upper()
 
-    f = c.get(d, 0.0)
-    h = a.get(d, 0.0)
+    f = c.get(_days, 0.0)
+    _hours = a.get(_days, 0.0)
 
     days = int(input("Enter your stay duration in days: "))
-    h *= days
-    total = f + h
+    _hours *= days
+    total = f + _hours
 
     print(f"Flight cost: USD {f:.2f}")
-    print(f"Hotel cost for {days} days: USD {h:.2f}")
+    print(f"Hotel cost for {days} days: USD {_hours:.2f}")
     print(f"Total: USD {total:.2f}")
 
     currency = input(f"Select your currency for final price estimation ({', '.join(b.keys())}): ")
 
-    p = total * b[currency]
-    print(f"Total in {currency}: {p:.2f}")
+    new = total * b[currency]
+    print(f"Total in {currency}: {new:.2f}")
 
 if __name__ == "__main__":
     main()