def StrLen(input_string, bitlength):
return BVV(len(input_string.value), bitlength)<EOL>
Create a concrete Bit-Vector of 32(?) bit size and as value the length of the string in bytes

:param input_string: the string we want to calculate the length
:param bitlength: bitlength of the bitvector representing the length of the string
:return: Bit vector holding the size of the string in bytes