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      "The message is in text \"Cardiff CDT meeting 2017\"\n",
      "The message is in Morse code \"-.-. .- .-. -.. .. ..-. ..-.   -.-. -.. -   -- . . - .. -. --.   ..--- ----- .---- --...\"\n",
      "The message is converted back to text \"cardiff cdt meeting 2017\"\n"
     ]
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    "########################################################################\n",
    "########################################################################\n",
    "# \n",
    "# Morse.py \n",
    "# write a function to return the Morse code for a text string\n",
    "# write a function to return the text string for a morse code string\n",
    "#\n",
    "########################################################################\n",
    "########################################################################\n",
    "\n",
    "# table that defines the ITU morse code standard for letters and numbers\n",
    "morse = { 'a' : '.-', \n",
    "          'b' : '-...', \n",
    "          'c' : '-.-.', \n",
    "          'd' : '-..', \n",
    "          'e' : '.', \n",
    "          'f' : '..-.', \n",
    "          'g' : '--.', \n",
    "          'h' : '....', \n",
    "          'i' : '..', \n",
    "          'j' : '.---', \n",
    "          'k' : '-.-', \n",
    "          'l' : '.-..', \n",
    "          'm' : '--', \n",
    "          'n' : '-.', \n",
    "          'o' : '---', \n",
    "          'p' : '.--.', \n",
    "          'q' : '--.-', \n",
    "          'r' : '.-.', \n",
    "          's' : '...', \n",
    "          't' : '-', \n",
    "          'u' : '..-', \n",
    "          'v' : '...-', \n",
    "          'w' : '.--', \n",
    "          'x' : '-..-', \n",
    "          'y' : '-.--', \n",
    "          'z' : '--..', \n",
    "          '1' : '.----', \n",
    "          '2' : '..---', \n",
    "          '3' : '...--', \n",
    "          '4' : '....-', \n",
    "          '5' : '.....', \n",
    "          '6' : '-....', \n",
    "          '7' : '--...', \n",
    "          '8' : '---..',\n",
    "          '9' : '----.', \n",
    "          '0' : '-----' }\n",
    "\n",
    "# Note: need a single space between letters and a double space between words\n",
    "\n",
    "def textToMorse(s):\n",
    "    \"\"\"Convert a text string s, containing letters numbers and spaces to Morse code\"\"\"\n",
    "    code = \"\"\n",
    "    for c in s: #loop over string s one character at a time\n",
    "        if c is ' ':\n",
    "            code += '  ' # double space between words\n",
    "        else:\n",
    "            code += morse[c.lower()]+' ' # single space between letters\n",
    "    while(code[-1] == ' '):\n",
    "        code = code[:-1] # remove last space(s) from message\n",
    "    return code \n",
    "\n",
    "def morseToText(s):\n",
    "     \"\"\"Convert a text string s, containing '.','-' and ' ' to text\"\"\"\n",
    "     # note need iteritems() below if using python2\n",
    "     revMorse = {v: k for k, v in morse.items()}\n",
    "     text = \"\" \n",
    "     newS = s.replace('  ',' X ') # indentify double spaces before splitting text\n",
    "     sList = newS.split() # split on white space so have each letter and X for spaces\n",
    "     for t in sList:\n",
    "         if t == 'X':\n",
    "             text += ' '\n",
    "         else:\n",
    "             text += revMorse[t]\n",
    "     return text\n",
    "\n",
    "message = \"Cardiff CDT meeting 2017\" \n",
    "\n",
    "print('The message is in text \"{}\"'.format(message))\n",
    "print('The message is in Morse code \"{}\"'.format(textToMorse(message)))\n",
    "print('The message is converted back to text \"{}\"'.format(morseToText(textToMorse(message))))\n"
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