Added more public API methods for _Memory object

Author: oleksandr-pavlyk

dpctl/memory/_memory.pyx

@@ -752,10 +752,28 @@ def as_usm_memory(obj):
 
 
 cdef api DPCTLSyclUSMRef get_usm_pointer(_Memory obj):
+    "Pointer of USM allocation"
     return obj.memory_ptr
 
-cdef api DPCTLSyclContextRef get_context(_Memory obj):
+cdef api DPCTLSyclContextRef get_context_ref(_Memory obj):
+    "Context reference to which USM allocation is bound"
     return obj.queue._context.get_context_ref()
 
+cdef api DPCTLSyclQueueRef get_queue_ref(_Memory obj):
+    """Queue associated with this allocation, used
+    for copying, population, etc."""
+    return obj.queue.get_queue_ref()
+
 cdef api size_t get_nbytes(_Memory obj):
+    "Size of the allocation in bytes."
     return <size_t>obj.nbytes
+
+cdef api object make_Memory(
+    DPCTLSyclUSMRef ptr,
+    size_t nbytes,
+    DPCTLSyclQueueRef QRef,
+    object owner
+):
+    return _Memory.create_from_usm_pointer_size_qref(
+        ptr, nbytes, QRef, memory_owner=owner
+    )