write the body of the following function

def digit_string_odd(L: List[int]) -> str:

"""Return a string that contains the digits in L up to (but not including) the first even digit. Use a while loop with appropriate conditions.

>>> digit_string_odd([1,2,3,4,5])

'1'

>>> digit_string_odd([1,3,3,4,5])

'133'

"""