refactoring: restore parser to backwards compatibility after refactoring (#5571)

Restore parser location after movings in #5552 for backwards
compatibility.

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---------

Co-authored-by: a <1@1.1>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

setup.py

@@ -41,7 +41,7 @@ def build_tables():
     print("Building lexer and parser tables.", file=sys.stderr)
     root_dir = os.path.abspath(os.path.dirname(__file__))
     sys.path.insert(0, root_dir)
-    from xonsh.parsers import Parser
+    from xonsh.parser import Parser
     from xonsh.parsers.completion_context import CompletionContextParser
 
     Parser(

tests/parsers/test_parser.py

@@ -6,7 +6,7 @@ import textwrap
 
 import pytest
 
-from xonsh.parsers import Parser
+from xonsh.parser import Parser
 from xonsh.parsers.ast import AST, Call, Pass, With, is_const_str
 from xonsh.parsers.fstring_adaptor import FStringAdaptor
 from xonsh.pytest.tools import (

xonsh/execer.py

@@ -6,7 +6,7 @@ import inspect
 import sys
 import types
 
-from xonsh.parsers import Parser
+from xonsh.parser import Parser
 from xonsh.parsers.ast import CtxAwareTransformer
 from xonsh.tools import (
     balanced_parens,

xonsh/parser.py

@@ -0,0 +1,17 @@
+"""Implements the xonsh parser."""
+
+from xonsh.lib.lazyasd import lazyobject
+from xonsh.platform import PYTHON_VERSION_INFO
+
+
+@lazyobject
+def Parser():
+    if PYTHON_VERSION_INFO > (3, 10):
+        from xonsh.parsers.v310 import Parser as p
+    elif PYTHON_VERSION_INFO > (3, 9):
+        from xonsh.parsers.v39 import Parser as p
+    elif PYTHON_VERSION_INFO > (3, 8):
+        from xonsh.parsers.v38 import Parser as p
+    else:
+        from xonsh.parsers.v36 import Parser as p
+    return p

xonsh/parsers/__init__.py

@@ -1,17 +1 @@
-"""Implements the xonsh parser."""
-
-from xonsh.lib.lazyasd import lazyobject
-from xonsh.platform import PYTHON_VERSION_INFO
-
-
-@lazyobject
-def Parser():
-    if PYTHON_VERSION_INFO > (3, 10):
-        from xonsh.parsers.v310 import Parser as p
-    elif PYTHON_VERSION_INFO > (3, 9):
-        from xonsh.parsers.v39 import Parser as p
-    elif PYTHON_VERSION_INFO > (3, 8):
-        from xonsh.parsers.v38 import Parser as p
-    else:
-        from xonsh.parsers.v36 import Parser as p
-    return p
+"""Implements the xonsh parsers."""