How to make a histogram from a list of strings

Very easy with Pandas.

import pandas
from collections import Counter
a = ['a', 'a', 'a', 'a', 'b', 'b', 'c', 'c', 'c', 'd', 'e', 'e', 'e', 'e', 'e']
letter_counts = Counter(a)
df = pandas.DataFrame.from_dict(letter_counts, orient="index")
df.plot(kind='bar')

Notice that Counter is making a frequency count, so our plot type is 'bar' not 'hist'.