Elastic beanstalk ebextensions / config：找不到包'libffi'

Question

这是我的配置：

我在.ebextensions中只有2个配置：01run.config和02do.config

.ebextensions / 01run.config

packages:
    yum:
        python27-devel: ''
        postgresql93-devel: ''
        pkgconfig: ''
        libffi-devel: ''
        libxslt-devel: ''
        libxml2-devel: ''

这有记录，我该怎么办？ 请帮我！谢谢!!

  Downloading/unpacking cffi==0.8.6 (from -r /opt/python/ondeck/app/requirements.txt (line 8))
  Running setup.py (path:/opt/python/run/venv/build/cffi/setup.py) egg_info for package cffi
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'libffi' found
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'libffi' found
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'libffi' found
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'libffi' found
    Package libffi was not found in the pkg-config search path.
    Perhaps you should add the directory containing `libffi.pc'
    to the PKG_CONFIG_PATH environment variable
    No package 'libffi' found