My python solution to the MorseCode test

MorseCode.py

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+"""
+Define exception raised when invalid morse code encountered
+"""
+class InvalidMorseCode(Exception):
+    pass
+
+"""
+Define MorseCode class which translates morse code to text
+"""
+class MorseCode():
+    """
+    define a static dictionary that contains the letters of the alphabet as the
+    key and the morse code as the value
+    """
+    translate_dict = {
+        'a' : '.-',
+        'b' : '-...',
+        'c' : '-.-.',
+        'd' : '-..',
+        'e' : '.',
+        'f' : '..-.',
+        'g' : '--.',
+        'h' : '....',
+        'i' : '..',
+        'j' : '.---',
+        'k' : '-.-',
+        'l' : '.-..',
+        'm' : '--',
+        'n' : '-.',
+        'o' : '---',
+        'p' : '.--.',
+        'q' : '--.-',
+        'r' : '.-.',
+        's' : '...',
+        't' : '-',
+        'u' : '..-',
+        'v' : '...-',
+        'w' : '.--',
+        'x' : '-..-',
+        'y' : '-.--',
+        'z' : '--..',
+        '0' : '-----',
+        '1' : '.----',
+        '2' : '..---',
+        '3' : '...--',
+        '4' : '....-',
+        '5' : '.....',
+        '6' : '-....',
+        '7' : '--...',
+        '8' : '---..',
+        '9' : '----.'
+        }
+
+    """
+    generate a dictionary where the morse code is key and the value is the
+    letter.  This makes it easier to translate the morse code.
+    """
+    morse_to_letter_dict = {code:letter for letter, code in \
+                            translate_dict.items()}
+
+    """
+    Define init function for MorseCode class.  Optional argument input sets
+    the morsecode to be translated to a default value
+    """
+    def __init__(self, input = "-..||---||--."):
+        self.morsecode = input
+
+    """
+    Define translate function which takes as input the morse code and returns
+    the translation.
+    """
+    def translate(self, input=None):
+
+        if input != None:
+            self.morsecode = input
+
+        #create a list of morse code elements to be translated
+        codes = self.morsecode.split('||')
+        #print(codes)
+        translated = ''
+
+        for code in codes:
+            # check to see if we have a valid morse code
+            if code in self.morse_to_letter_dict.keys():
+                #append the letter corresponding to the morse code to the
+                #translation
+                translated += self.morse_to_letter_dict[code]
+            elif code == '':
+                #if we encounter an empty code then translate to a space
+                translated += ' '
+            else:
+                #print an error if we encounter an invalid code
+                #print("ERROR: code not found!")
+                raise InvalidMorseCode
+
+        return translated
+
+    """
+    Define method to set the morse code to be translated
+    """
+    def set_morsecode(self, input):
+        self.morsecode = input
+
+    """
+    Define method to get the morse code which is being translated
+    """
+    def get_morsecode(self):
+        return self.morsecode
+
+# define a main function which executes some tests on this module
+def main():
+
+    # define a dictionary that contains morse code with expected translation
+    test_dict = {
+        '-..||---||--.' : 'dog',
+        '....||.||.-..||.-..||---||||.--||---||.-.||.-..||-..' : 'hello world',
+        '...||---||...' : 'sos'
+        }
+
+    morsecode1 = MorseCode()
+    try:
+        """
+        translate each morse code in the test dictionary and verify that the
+        MorseCode class returns the correct translation
+        """
+        for morse, word in test_dict.items():
+            correct = "Correctly translated {morse} into {word}"
+            incorrect = """ERROR: Incorrectly translated {morse}.\r\n
+            Expected: {expected} but instead got {actual}"""
+            if morsecode1.translate(morse) != word:
+                print(incorrect.format(morse = morse, \
+                                       expected = word, \
+                                       actual = morsecode1.translate(morse)))
+            else:
+                print(correct.format(morse = morse, word = word))
+    except InvalidMorseCode:
+        print("ERROR: Invalid morse code exception raised!")
+
+    """
+    Verify that the InvalidMorseCode exception is raised when an invalid
+    morse code sequence is provided
+    """
+    try:
+        invalid_morse_code = '----'
+        morsecode1.translate(invalid_morse_code)
+        print("ERROR: invalid morse code exception not raised!")
+    except InvalidMorseCode:
+        print("Invalid morse code exception raised correctly")
+
+# execute main function only if this code is run as a script
+if __name__ == "__main__":
+    main()
+

inputfile.txt

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+-..||---||--.
+....||.||.-..||.-..||---||||.--||---||.-.||.-..||-..
+...||---||...
+....||..||.-.||.||||.-||-.||--.||.||.-..||---

translatefile.py

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+from MorseCode import MorseCode
+from MorseCode import InvalidMorseCode
+import re
+import argparse
+
+parser = argparse.ArgumentParser()
+parser.add_argument("file",help="input file with morse code to translate")
+args = parser.parse_args()
+
+morsecode1 = MorseCode()
+
+with open(args.file, 'r') as input_file:
+    for line in input_file:
+        #strip out CR and LF characters at start and end of strings
+        cleanline = line.strip()
+        try:
+            print(morsecode1.translate(cleanline))
+        except InvalidMorseCode:
+            print("Error: invalid morse code encountered!")
+
+