How to access a string from C code with ctypes

I have a simple C file:

char *initializetest()
{
    char *test = malloc(1000);
    return test;
}

int searchtest(char *test)
{
    strcpy(test, "test");
    return 0;
}

main()
{
    char *test = initializetest();
    searchtest(test);
    printf("%s\n", test);
}

and Python file:

from ctypes import *

class Test(object):
    def __init__(self):
        self.test_library=CDLL("test.so")
        self.test_initialize = self.test_library.initializetest
        self.test_search = self.test_library.searchtest
        self.test_search.restype=c_int
        self.m = self.test_initialize()

    def search(self):
        self.test_search(self.m)
        print self.m

r = Test()
print r.search()

How to get "test" string in Python?