Revert "Updates according to PR comments"

This reverts commit 43b95607.

gpMgmt/bin/gpexpand

@@ -829,8 +829,8 @@ SELECT pg_catalog.pg_relation_filepath(c.oid)
                 continue
             # a pathname is like './pg_tblspc/16385/GPDB_7_301911081/16386/6052_vm'
             # we need to change it to './16385/<dummyDBID>/GPDB_7_301911081/16386/6052_vm'
-            seps = pathname.split(os.sep)
-            pathname = os.sep.join([seps[2], str(dummyDBID)] + seps[3:])
+            pathname = os.sep.join([pathname.split(os.sep)[2], str(dummyDBID)] +
+                                   pathname.split(os.sep)[3:])
             full_excludes.append(os.path.join(tablespace_template_dir,
                                               pathname))
 
@@ -855,12 +855,7 @@ SELECT pg_catalog.pg_relation_filepath(c.oid)
             # so it is safe to use a check-and-create style to create dirs.
             if not os.path.isdir(dirname):
                 os.makedirs(dirname)
-            # the file should not already exist, however in case it does, which
-            # indicates an error in the excluding logic, raise an error.
-            if os.path.exists(fullname):
-                self.logger.error("Could not exclude file '%s' from the template: file exists" % fullname)
-                raise Exception('Invalid exclude list')
-            open(fullname, 'ab')
+            open(fullname, 'wb')
 
         with open(os.path.join(self.tempDir,
                                "pg_tblspc",
@@ -1026,13 +1021,7 @@ SELECT pg_catalog.pg_relation_filepath(c.oid)
                 # so it is safe to use a check-and-create style to create dirs.
                 if not os.path.isdir(dirname):
                     os.makedirs(dirname)
-                # the file should not already exist, however in case it does,
-                # which indicates an error in the excluding logic, raise an
-                # error.
-                if os.path.exists(fullname):
-                    self.logger.error("Could not exclude file '%s' from the template: file exists" % fullname)
-                    raise Exception('Invalid exclude list')
-                open(fullname, 'ab')
+                open(fullname, 'wb')
 
     def _tar_template(self):
         """Tars up the template files"""