In this kata, we're going to create the function `nato` that takes a `word` and returns a string that spells the word using the [NATO phonetic alphabet](https://en.wikipedia.org/wiki/NATO_phonetic_alphabet).
There should be a space between each word in the returned string, and the first letter of each word should be capitalized.
For those of you that don't want your fingers to bleed, this kata already has a dictionary typed out for you.
``` python
nato("Banana") # == "Bravo Alpha November Alpha November Alpha"
```
``` ruby
nato("Banana") # == "Bravo Alpha November Alpha November Alpha"
```
letters =  {
    "A": "Alpha",  "B": "Bravo",   "C": "Charlie",
    "D": "Delta",  "E": "Echo",    "F": "Foxtrot",
    "G": "Golf",   "H": "Hotel",   "I": "India",
    "J": "Juliett","K": "Kilo",    "L": "Lima",
    "M": "Mike",   "N": "November","O": "Oscar",
    "P": "Papa",   "Q": "Quebec",  "R": "Romeo",
    "S": "Sierra", "T": "Tango",   "U": "Uniform",
    "V": "Victor", "W": "Whiskey", "X": "X-ray",
    "Y": "Yankee", "Z": "Zulu"
  }
  
def nato(word):
    return " ".join([letters[c] for c in word.upper()])
letters =  {
    "A": "Alpha",  "B": "Bravo",   "C": "Charlie",
    "D": "Delta",  "E": "Echo",    "F": "Foxtrot",
    "G": "Golf",   "H": "Hotel",   "I": "India",
    "J": "Juliett","K": "Kilo",    "L": "Lima",
    "M": "Mike",   "N": "November","O": "Oscar",
    "P": "Papa",   "Q": "Quebec",  "R": "Romeo",
    "S": "Sierra", "T": "Tango",   "U": "Uniform",
    "V": "Victor", "W": "Whiskey", "X": "X-ray",
    "Y": "Yankee", "Z": "Zulu"
  }
  
def nato(word):
    return " ".join([letters[c] for c in word.upper()])