Could not find gflagsConfig.cmake

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i was trying to make some pkg which uses gflags, but catkin_make gave me the following error

CMake Error at utils/src/CMakeLists.txt:23 (find_package):
  By not providing "Findgflags.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "gflags", but
  CMake did not find one.

  Could not find a package configuration file provided by "gflags" with any
  of the following names:

    gflagsConfig.cmake
    gflags-config.cmake

  Add the installation prefix of "gflags" to CMAKE_PREFIX_PATH or set
  "gflags_DIR" to a directory containing one of the above files.  If "gflags"
      provides a separate development package or SDK, be sure it has been
      installed.