diff --git a/working build.py b/working build.py
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+++ b/working build.py	
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+# Copyright (c) 2018 Yubico AB
+# All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or
+#   without modification, are permitted provided that the following
+#   conditions are met:
+#
+#    1. Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#    2. Redistributions in binary form must reproduce the above
+#       copyright notice, this list of conditions and the following
+#       disclaimer in the documentation and/or other materials provided
+#       with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+"""
+Connects to the first FIDO device found (starts from USB, then looks into NFC),
+creates a new credential for it, and authenticates the credential.
+This works with both FIDO 2.0 devices as well as with U2F devices.
+On Windows, the native WebAuthn API will be used.
+"""
+from fido2.hid import CtapHidDevice
+from fido2.client import Fido2Client, WindowsClient, UserInteraction
+from fido2.server import Fido2Server
+from getpass import getpass
+import sys
+import ctypes
+
+
+# Handle user interaction
+class CliInteraction(UserInteraction):
+    def prompt_up(self):
+        print("\nTouch your authenticator device now...\n")
+
+    def request_pin(self, permissions, rd_id):
+        return getpass("Enter PIN: ")
+
+    def request_uv(self, permissions, rd_id):
+        print("User Verification required.")
+        return True
+
+
+uv = "discouraged"
+
+if WindowsClient.is_available() and not ctypes.windll.shell32.IsUserAnAdmin():
+    # Use the Windows WebAuthn API if available, and we're not running as admin
+    client = WindowsClient("https://example.com")
+else:
+    # Locate a device
+    dev = next(CtapHidDevice.list_devices(), None)
+    if dev is not None:
+        print("Use USB HID channel.")
+    else:
+        try:
+            from fido2.pcsc import CtapPcscDevice
+
+            dev = next(CtapPcscDevice.list_devices(), None)
+            print("Use NFC channel.")
+        except Exception as e:
+            print("NFC channel search error:", e)
+
+    if not dev:
+        print("No FIDO device found")
+        sys.exit(1)
+
+    # Set up a FIDO 2 client using the origin https://example.com
+    client = Fido2Client(dev, "https://example.com", user_interaction=CliInteraction())
+
+    # Prefer UV if supported and configured
+    if client.info.options.get("uv") or client.info.options.get("pinUvAuthToken"):
+        uv = "preferred"
+        print("Authenticator supports User Verification")
+
+
+server = Fido2Server({"id": "example.com", "name": "Example RP"}, attestation="direct")
+
+user = {"id": b"user_id", "name": "A. User"}
+
+
+# Prepare parameters for makeCredential
+create_options, state = server.register_begin(
+    user, user_verification=uv, authenticator_attachment="cross-platform"
+)
+
+# Create a credential
+result = client.make_credential(create_options["publicKey"])
+
+# Complete registration
+auth_data = server.register_complete(
+    state, result.client_data, result.attestation_object
+)
+credentials = [auth_data.credential_data]
+
+print("New credential created!")
+
+print("CLIENT DATA:", result.client_data)
+print("ATTESTATION OBJECT:", result.attestation_object)
+print()
+print("CREDENTIAL DATA:", auth_data.credential_data)
+
+
+# Prepare parameters for getAssertion
+request_options, state = server.authenticate_begin(credentials, user_verification=uv)
+
+# Authenticate the credential
+result = client.get_assertion(request_options["publicKey"])
+
+# Only one cred in allowCredentials, only one response.
+result = result.get_response(0)
+
+# Complete authenticator
+server.authenticate_complete(
+    state,
+    credentials,
+    result.credential_id,
+    result.client_data,
+    result.authenticator_data,
+    result.signature,
+)
+
+print("Credential authenticated!")
+
+print("CLIENT DATA:", result.client_data)
+print()
+print("AUTH DATA:", result.authenticator_data)
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