Fixed _error.py and _placeholder_handler.py

Author: tomuben

exasol/error/_error.py

@@ -9,15 +9,15 @@
 )
 
 from exasol.error import _exa_error
+from exasol.error._error_message_builder import (
+    ErrorMessageBuilder,
+    InvalidErrorCode,
+)
 from exasol.error._internal_errors import (
     INVALID_ERROR_CODE,
     LIBRARY_ERRORS,
     UNKNOWN_EXCEPTION_OCCURED,
 )
-from exasol.error._error_message_builder import (
-    ErrorMessageBuilder,
-    InvalidErrorCode,
-)
 
 
 @dataclass(frozen=True)
@@ -36,7 +36,7 @@ def __init__(
     ) -> None:
         # This function maybe flattened into or moved out of the constructor in the future.
         def build_error(code, msg, mitigations, params) -> ErrorMessageBuilder:
-            builder = exa_error.ExaError.message_builder(code)
+            builder = _exa_error.ExaError.message_builder(code)
             builder.message(msg)
 
             for mitigation in mitigations:

exasol/error/_placeholder_handler.py

@@ -4,7 +4,7 @@
     Iterable,
 )
 
-from exasol.error.placeholder import Placeholder
+from exasol.error._placeholder import Placeholder
 
 
 class PlaceholderHandler: