WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:1129)'))': /simple/keras/ WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:1129)'))': /simple/keras/ WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:1129)'))': /simple/keras/ WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:1129)'))': /simple/keras/ WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:1129)'))': /simple/keras/ Could not fetch URL https://pypi.org/simple/keras/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/keras/ (Caused by SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:1129)'))) - skipping ERROR: Could not find a version that satisfies the requirement keras (from versions: none) ERROR: No matching distribution found for keras

这个错误可能是由于网络问题导致的。您可以尝试使用以下命令安装keras库：

pip install --trusted-host pypi.org --trusted-host files.pythonhosted.org keras

这个命令会添加一些信任的主机，以便更好地访问pypi.org和files.pythonhosted.org。如果您使用的是anaconda，可以使用以下命令安装：

conda install -c conda-forge keras

这个命令将从conda-forge渠道安装keras库。如果您的网络连接不稳定，可以尝试多次运行上述命令，直到成功为止。