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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Importing qt_compat when no Qt binding is installed fails with NameError instead of ImportError","articleBody":"\u003c!--To help us understand and resolve your issue, please fill out the form to the best of your ability.--\u003e\r\n\u003c!--You can feel free to delete the sections that do not apply.--\u003e\r\n\r\n### Bug report\r\n\r\n**Bug summary**\r\n\r\nSee title.\r\n\r\n**Code for reproduction**\r\n\r\nIn a clean venv with matplotlib (HEAD) installed and no qt binding installed, import `matplotlib.backends.qt_compat`.\r\n\r\n**Actual outcome**\r\n\r\n```\r\nTraceback (most recent call last):\r\n  File \"\u003cstring\u003e\", line 1, in \u003cmodule\u003e\r\n  File \"/home/antony/src/extern/matplotlib/lib/matplotlib/backends/qt_compat.py\", line 197, in \u003cmodule\u003e\r\n    QtCore.Signal = QtCore.pyqtSignal\r\nNameError: name 'QtCore' is not defined\r\n```\r\n\r\n**Expected outcome**\r\n\r\nAn ImportError.\r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system:\r\n  * Matplotlib version: master\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`):\r\n  * Python version:\r\n  * Jupyter version (if applicable):\r\n  * Other libraries: \r\n\r\n---\r\n\r\nIntroduced by #11500 (I think).\r\n#9993 fixes the issue and is ready to go.","author":{"url":"https://github.com/anntzer","@type":"Person","name":"anntzer"},"datePublished":"2018-07-11T09:16:54.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/11629/matplotlib/issues/11629"}