'field(address, field) => a structure field.
Leak a field from a structure.
Arguments:
address(int): Base address to calculate offsets from
field(obj):   Instance of a ctypes field
Return Value:
The type of the return value will be dictated by
the type of ``field``.'

def field(self, address, obj):

    size = obj.size
    offset = obj.offset
    data = self.n((address + offset), size)
    if (not data):
        return None
    return unpack(data, (size * 8))
