这道题什么意思啊，没看懂，请帮我讲一下吧……

The len() function is used to count how many characters a string contains.
Get the first half of the string stored in the variable 'phrase'.
Note: Remember about type conversion.

phrase = """
It is a really long string
triple-quoted strings are used
to define multi-line strings
"""
first_half = ???????
print(first_half)

就是问？？？那里写什么，我一直没搞懂first_half指什么。