@@ -18,12 +18,9 @@
 )
 
 import google.api_core as api_core
-import sys
 
 __version__ = package_version.__version__
 
-from importlib import metadata
-
 # PEP 0810: Explicit Lazy Imports
 # Python 3.15+ natively intercepts and defers these imports.
 # Developers can disable this behavior and force eager imports.
@@ -53,89 +50,6 @@
 from .types.video_classification import VideoClassificationPredictionInstance
 from .types.video_object_tracking import VideoObjectTrackingPredictionInstance
 
-if hasattr(api_core, "check_python_version") and hasattr(
-    api_core, "check_dependency_versions"
-):  # pragma: NO COVER
-    api_core.check_python_version("google.cloud.aiplatform.v1.schema.predict.instance_v1")  # type: ignore
-    api_core.check_dependency_versions("google.cloud.aiplatform.v1.schema.predict.instance_v1")  # type: ignore
-else:  # pragma: NO COVER
-    # An older version of api_core is installed which does not define the
-    # functions above. We do equivalent checks manually.
-    try:
-        import warnings
-
-        _py_version_str = sys.version.split()[0]
-        _package_label = "google.cloud.aiplatform.v1.schema.predict.instance_v1"
-        if sys.version_info < (3, 10):
-            warnings.warn(
-                "You are using a non-supported Python version "
-                + f"({_py_version_str}).  Google will not post any further "
-                + f"updates to {_package_label} supporting this Python version. "
-                + "Please upgrade to the latest Python version, or at "
-                + f"least to Python 3.10, and then update {_package_label}.",
-                FutureWarning,
-            )
-
-        def parse_version_to_tuple(version_string: str):
-            """Safely converts a semantic version string to a comparable tuple of integers.
-            Example: "6.33.5" -> (6, 33, 5)
-            Ignores non-numeric parts and handles common version formats.
-            Args:
-                version_string: Version string in the format "x.y.z" or "x.y.z<suffix>"
-            Returns:
-                Tuple of integers for the parsed version string.
-            """
-            parts = []
-            for part in version_string.split("."):
-                try:
-                    parts.append(int(part))
-                except ValueError:
-                    # If it's a non-numeric part (e.g., '1.0.0b1' -> 'b1'), stop here.
-                    # This is a simplification compared to 'packaging.parse_version', but sufficient
-                    # for comparing strictly numeric semantic versions.
-                    break
-            return tuple(parts)
-
-        def _get_version(dependency_name):
-            try:
-                version_string: str = metadata.version(dependency_name)
-                parsed_version = parse_version_to_tuple(version_string)
-                return (parsed_version, version_string)
-            except Exception:
-                # Catch exceptions from metadata.version() (e.g., PackageNotFoundError)
-                # or errors during parse_version_to_tuple
-                return (None, "--")
-
-        _dependency_package = "google.protobuf"
-        _next_supported_version = "6.33.5"
-        _next_supported_version_tuple = (6, 33, 5)
-        _recommendation = " (we recommend 7.x)"
-        (_version_used, _version_used_string) = _get_version(_dependency_package)
-        if _version_used and _version_used < _next_supported_version_tuple:
-            warnings.warn(
-                f"Package {_package_label} depends on "
-                + f"{_dependency_package}, currently installed at version "
-                + f"{_version_used_string}. Future updates to "
-                + f"{_package_label} will require {_dependency_package} at "
-                + f"version {_next_supported_version} or higher{_recommendation}."
-                + " Please ensure "
-                + "that either (a) your Python environment doesn't pin the "
-                + f"version of {_dependency_package}, so that updates to "
-                + f"{_package_label} can require the higher version, or "
-                + "(b) you manually update your Python environment to use at "
-                + f"least version {_next_supported_version} of "
-                + f"{_dependency_package}.",
-                FutureWarning,
-            )
-    except Exception:
-        warnings.warn(
-            "Could not determine the version of Python "
-            + "currently being used. To continue receiving "
-            + "updates for {_package_label}, ensure you are "
-            + "using a supported version of Python; see "
-            + "https://devguide.python.org/versions/"
-        )
-
 __all__ = (
     "ImageClassificationPredictionInstance",
     "ImageObjectDetectionPredictionInstance",
@@ -147,3 +61,8 @@ def _get_version(dependency_name):
     "VideoClassificationPredictionInstance",
     "VideoObjectTrackingPredictionInstance",
 )
+
+api_core.check_python_version("google.cloud.aiplatform.v1.schema.predict.instance_v1")
+api_core.check_dependency_versions(
+    "google.cloud.aiplatform.v1.schema.predict.instance_v1"
+)
@@ -0,0 +1,263 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+"""A compatibility module for older versions of google-api-core."""
+
+import os
+import json
+
+from typing import Any, Dict, List, Optional, Tuple
+
+from google.api_core import path_template
+from google.api_core.universe import EmptyUniverseError
+from google.auth.exceptions import MutualTLSChannelError
+from google.protobuf import json_format
+from urllib.parse import urlparse, urlunparse
+
+try:
+    # note: `#type: ignore` is added because the return type for `should_use_client_cert`
+    # is different than that of the fallback implementation below. This will be removed once
+    # we bump the minimum supported version of google-auth.
+    from google.auth.transport.mtls import should_use_client_cert  # type: ignore
+except ImportError:  # pragma: NO COVER
+
+    def should_use_client_cert():
+        """Returns whether client certificate should be used for mTLS."""
+        use_client_cert = os.getenv(
+            "GOOGLE_API_USE_CLIENT_CERTIFICATE", "false"
+        ).lower()
+        if use_client_cert not in ("true", "false"):
+            raise ValueError(
+                "Environment variable `GOOGLE_API_USE_CLIENT_CERTIFICATE` must be"
+                " either `true` or `false`"
+            )
+        return use_client_cert == "true"
+
+
+def read_environment_variables():
+    """Returns the environment variables used by the client.
+
+    Returns:
+        Tuple[bool, str, str]: returns the GOOGLE_API_USE_CLIENT_CERTIFICATE,
+        GOOGLE_API_USE_MTLS_ENDPOINT, and GOOGLE_CLOUD_UNIVERSE_DOMAIN environment variables.
+
+    Raises:
+        ValueError: If GOOGLE_API_USE_CLIENT_CERTIFICATE is not
+            any of ["true", "false"].
+        google.auth.exceptions.MutualTLSChannelError: If GOOGLE_API_USE_MTLS_ENDPOINT
+            is not any of ["auto", "never", "always"].
+    """
+    use_client_cert = should_use_client_cert()
+    use_mtls_endpoint = os.getenv("GOOGLE_API_USE_MTLS_ENDPOINT", "auto").lower()
+    universe_domain_env = os.getenv("GOOGLE_CLOUD_UNIVERSE_DOMAIN")
+    if use_mtls_endpoint not in ("auto", "never", "always"):
+        raise MutualTLSChannelError(
+            "Environment variable `GOOGLE_API_USE_MTLS_ENDPOINT` must be `never`,"
+            " `auto` or `always`"
+        )
+    return use_client_cert, use_mtls_endpoint, universe_domain_env
+
+
+DEFAULT_UNIVERSE = "googleapis.com"
+
+try:
+    from google.api_core.universe import get_default_mtls_endpoint
+except ImportError:  # pragma: NO COVER
+
+    def get_default_mtls_endpoint(api_endpoint: Optional[str]) -> Optional[str]:
+        """Converts api endpoint to mTLS endpoint.
+
+        Convert "*.sandbox.googleapis.com" and "*.googleapis.com" to
+        "*.mtls.sandbox.googleapis.com" and "*.mtls.googleapis.com" respectively.
+        Other URLs (including those that do not match these domain suffixes or
+        already contain '.mtls.') are passed through as-is.
+
+        Args:
+            api_endpoint (Optional[str]): the api endpoint to convert.
+
+        Returns:
+            Optional[str]: converted mTLS api endpoint.
+        """
+        if not api_endpoint or ".mtls." in api_endpoint.lower():
+            return api_endpoint
+
+        has_scheme = "://" in api_endpoint
+        if not has_scheme:
+            parsed = urlparse("//" + api_endpoint)
+        else:
+            parsed = urlparse(api_endpoint)
+
+        host = parsed.hostname
+        if not host:
+            return api_endpoint
+
+        port = f":{parsed.port}" if parsed.port else ""
+
+        lowered_host = host.lower()
+        suffix_sandbox = ".sandbox.googleapis.com"
+        suffix_google = ".googleapis.com"
+        if lowered_host.endswith(suffix_sandbox):
+            new_host = host[: -len(suffix_sandbox)] + ".mtls.sandbox.googleapis.com"
+        elif lowered_host.endswith(suffix_google):
+            new_host = host[: -len(suffix_google)] + ".mtls.googleapis.com"
+        else:
+            return api_endpoint
+
+        netloc = new_host + port
+        new_parsed = parsed._replace(netloc=netloc)
+
+        if not has_scheme:
+            return urlunparse(new_parsed)[2:]
+        else:
+            return urlunparse(new_parsed)
+
+
+try:
+    from google.api_core.universe import get_api_endpoint
+except ImportError:  # pragma: NO COVER
+
+    def get_api_endpoint(
+        api_override: Optional[str],
+        universe_domain: str,
+        default_universe: str,
+        default_mtls_endpoint: Optional[str],
+        default_endpoint_template: str,
+        use_mtls: bool,
+    ) -> str:
+        """Return the API endpoint used by the client.
+
+        Args:
+            api_override (Optional[str]): The API endpoint override. If specified,
+                this is always returned.
+            universe_domain (str): The universe domain used by the client.
+            default_universe (str): The default universe domain.
+            default_mtls_endpoint (Optional[str]): The default mTLS endpoint.
+            default_endpoint_template (str): The default endpoint template containing
+                a placeholder `{UNIVERSE_DOMAIN}`.
+            use_mtls (bool): Whether to use the mTLS endpoint.
+
+        Returns:
+            str: The API endpoint to be used by the client.
+
+        Raises:
+            google.auth.exceptions.MutualTLSChannelError: If mTLS is requested but
+                not supported in the configured universe domain.
+            ValueError: If mTLS is requested but no mTLS endpoint is available.
+        """
+        if api_override is not None:
+            return api_override
+
+        if use_mtls:
+            if universe_domain.lower() != default_universe.lower():
+                raise MutualTLSChannelError(
+                    f"mTLS is not supported in any universe other than {default_universe}."
+                )
+            if not default_mtls_endpoint:
+                raise ValueError("mTLS endpoint is not available.")
+            return default_mtls_endpoint
+        else:
+            return default_endpoint_template.format(UNIVERSE_DOMAIN=universe_domain)
+
+
+try:
+    from google.api_core.universe import get_universe_domain
+except ImportError:  # pragma: NO COVER
+
+    def get_universe_domain(
+        *potential_universes: Optional[str],
+        default_universe: str,
+    ) -> str:
+        """Return the universe domain used by the client.
+
+        Args:
+            *potential_universes (Optional[str]): Potential universe domains in order of preference.
+            default_universe (str): The default universe domain.
+
+        Returns:
+            str: The universe domain to be used by the client.
+
+        Raises:
+            EmptyUniverseError: If the resolved universe domain is an empty string.
+        """
+        resolved = next(
+            (x.strip() for x in potential_universes if x is not None),
+            default_universe,
+        )
+
+        if not resolved:
+            raise EmptyUniverseError()
+        return resolved
+
+
+try:
+    from google.api_core.rest_helpers import transcode_request  # type: ignore
+except ImportError:  # pragma: NO COVER
+
+    def transcode_request(
+        http_options: List[Dict[str, str]],
+        request: Any,
+        required_fields_default_values: Optional[Dict[str, Any]] = None,
+        rest_numeric_enums: bool = False,
+    ) -> Tuple[Dict[str, Any], Optional[str], Dict[str, Any]]:
+        """Transcodes a request into HTTP method, URI, body, and query parameters.
+
+        Args:
+            http_options (List[Dict[str, str]]): List of HTTP transcoding rules.
+            request (Any): The protobuf or proto-plus request message.
+            required_fields_default_values (Optional[Dict[str, Any]]): Dictionary
+                of required fields default values to merge into query parameters if missing.
+            rest_numeric_enums (bool): Whether to encode enums as integers.
+
+        Returns:
+            Tuple[Dict[str, Any], Optional[str], Dict[str, Any]]: A tuple containing:
+                - The raw transcoded request dictionary (containing keys like 'uri', 'method').
+                - The serialized request body JSON string, or None if no body.
+                - The query parameters dictionary.
+        """
+        if request is None:
+            raise TypeError("request cannot be None")
+
+        # Convert proto-plus message to its underlying protobuf message if needed
+        pb_request = getattr(request, "_pb", request)
+
+        transcoded_request = path_template.transcode(http_options, pb_request)
+
+        body_json = None
+        if transcoded_request.get("body") is not None:
+            body_json = json_format.MessageToJson(
+                transcoded_request["body"],
+                use_integers_for_enums=rest_numeric_enums,
+            )
+
+        query_params_json = {}
+        if transcoded_request.get("query_params") is not None:
+            query_params_json = json.loads(
+                json_format.MessageToJson(
+                    transcoded_request["query_params"],
+                    use_integers_for_enums=rest_numeric_enums,
+                )
+            )
+
+        # If required_fields_default_values is provided, we merge default values for missing
+        # required fields into the query parameters.
+        if required_fields_default_values:
+            for k, v in required_fields_default_values.items():
+                if k not in query_params_json:
+                    query_params_json[k] = v
+
+        if rest_numeric_enums:
+            query_params_json["$alt"] = "json;enum-encoding=int"
+
+        return transcoded_request, body_json, query_params_json