Changed argument parsing to method.

src/main.py

@@ -12,26 +12,24 @@ import matplotlib.pyplot as plt
 # Import custom image filter library
 import filters as flt
 
-parser = ap.ArgumentParser(prog='main.py',
+class app:
-                           description='loads and stores image')
+    def __init__(self):
+        self.parse_arguments()
+        self.input_file = self.args.input_file
+        self.output_file = self.args.output_file
+        self.img = plt.imread(self.input_file)
+        self.dpi = self.args.dpi
+        self.filters = self.args.filters
+        self.apply_filters()
 
+    def parse_arguments(self):
+        parser = ap.ArgumentParser(prog='main.py', description='loads and stores image')
         parser.add_argument("-i", "--input_file", help="Input file", required=True)
         parser.add_argument("-o", "--output_file", help="Output file", required=True)
         parser.add_argument('-d', "--dpi", type=int, required=True)
         #parser.add_argument( '-s', '--size')
         parser.add_argument('filters', type=str, nargs='*')
-
+        self.args = parser.parse_args()
-args = parser.parse_args()
-
-
-class app:
-    def __init__(self, input_file, output_file, dpi, filters):
-        self.input_file = input_file
-        self.output_file = output_file
-        self.img = plt.imread(self.input_file)
-        self.dpi = dpi
-        self.filters = filters
-        self.apply_filters()
 
     def filter_factory(self, filter_name):
         if filter_name == "average":
@@ -53,5 +51,4 @@ class app:
         # Save processed image
         plt.savefig(self.output_file)
 
-
+app = app()
-app = app(args.input_file, args.output_file, args.dpi, args.filters)