The fifth-generation (5G) cellular networks incorporate a large variety of technologies in order to address very distinct use cases. Assessing these technologies and investigating future alternatives is complicated when one relies only on simulators. 5G testbeds are an important alternative to simulators and many have been recently described, emphasizing aspects such as cloud functionalities, management and orchestration. This work presents a 5G mobile network testbed with a virtualized and orchestrated structure using containers, which focuses on integration to artificial intelligence (AI) applications. The presented testbed uses open-source technologies to deploy and orchestrate the virtual network functions (VNFs) to flexibly create various mobile network scenarios, with distinct fronthaul and backhaul topologies. Distinctive features of the testbed are its relatively low cost and the support to using AI for optimizing the network performance. The paper explains how to deploy the testbed structure and reproduce the presented results with the provided code. AI-based radio access network (RAN) slicing and VNF placement are used as examples of the testbed capabilities.