Write a Python program that reads a list of strings and sorts them by the number of characters in each string.
['foo', 'bar', 'baz', 'foobar', 'beer', 'wine']
list_of_strings = ['foo', 'bar', 'baz', 'foobar', 'beer', 'wine']

# sort strings by length
list_of_strings.sort(key=len)

# print sorted list
print(list_of_strings)