diff --git a/libarchive/_libarchive.i b/libarchive/_libarchive.i
index 88a2228..1dccbc6 100644
--- a/libarchive/_libarchive.i
+++ b/libarchive/_libarchive.i
@@ -524,11 +524,11 @@ extern const char	*archive_error_string(struct archive *);
 
 PyObject *archive_read_data_into_str(struct archive *archive, int len) {
     PyObject *str = NULL;
-    if (!(str = PyUnicode_FromStringAndSize(NULL, len))) {
+    if (!(str = PyBytes_FromStringAndSize(NULL, len))) {
         PyErr_SetString(PyExc_MemoryError, "could not allocate string.");
         return NULL;
     }
-    if (len != archive_read_data(archive, PyUnicode_AS_DATA(str), len)) {
+    if (len != archive_read_data(archive, PyBytes_AS_STRING(str), len)) {
         PyErr_SetString(PyExc_RuntimeError, "could not read requested data.");
         return NULL;
     }
diff --git a/libarchive/_libarchive_wrap.c b/libarchive/_libarchive_wrap.c
index 61d339f..d13a0e1 100644
--- a/libarchive/_libarchive_wrap.c
+++ b/libarchive/_libarchive_wrap.c
@@ -3196,11 +3196,11 @@ SWIG_AsVal_unsigned_SS_short (PyObject * obj, unsigned short *val)
 
 PyObject *archive_read_data_into_str(struct archive *archive, int len) {
     PyObject *str = NULL;
-    if (!(str = PyUnicode_FromStringAndSize(NULL, len))) {
+    if (!(str = PyBytes_FromStringAndSize(NULL, len))) {
         PyErr_SetString(PyExc_MemoryError, "could not allocate string.");
         return NULL;
     }
-    if (len != archive_read_data(archive, PyUnicode_AS_DATA(str), len)) {
+    if (len != archive_read_data(archive, PyBytes_AS_STRING(str), len)) {
         PyErr_SetString(PyExc_RuntimeError, "could not read requested data.");
         return NULL;
     }