#return a dictionary of counts of letters in a string
def countLetters(text):
    counts = {}
    for char in text:
        if char.isalpha():
            low = char.lower()
            if low in counts:
                counts[low] = counts[low] + 1
            else:
                counts[low] = 1

    return counts

#testing
letter_counts = countLetters("The quick brown fox jumps over the lazy dog.")
keys = list(letter_counts.keys())
keys.sort()
for char in keys:
    print(char, letter_counts[char])