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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def configure_cmake(self):
 """Create CMake instance and execute configure step """

        cmake = CMake(self)
        cmake.definitions["FLATBUFFERS_BUILD_TESTS"] = False
        cmake.definitions["FLATBUFFERS_BUILD_SHAREDLIB"] = self.options.shared
        cmake.definitions["FLATBUFFERS_BUILD_FLATLIB"] = not self.options.shared
        cmake.configure()
        return cmake