新手求指教，docker build时无法下载依赖库

路人乙丙丁

#3 [internal] load metadata for docker.io/library/python:3.9-slim
#3 ERROR: unexpected status from HEAD request to https://docker.fnnas.com/v2/library/python/manifests/3.9-slim?ns=docker.io: 401 Unauthorized
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> [internal] load metadata for docker.io/library/python:3.9-slim:
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Dockerfile:1

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1 | >>> FROM python:3.9-slim

2 |

3 | # 安装cron

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failed to solve: python:3.9-slim: failed to resolve source metadata for docker.io/library/python:3.9-slim: unexpected status from HEAD request to https://docker.fnnas.com/v2/library/python/manifests/3.9-slim?ns=docker.io: 401 Unauthorized