我在安装googleapi客户端时遇到以下错误，之前我是根据项目需要安装的guzzle6。现在我正在尝试将两个项目合并到一个项目中。

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Installation request for google/apiclient 2.0 -> satisfiable by google/apiclient[v2.0.0].
    - google/apiclient v2.0.0 requires google/auth 0.8 -> satisfiable by google/auth[v0.8].
    - Conclusion: don't install guzzlehttp/psr7 1.3.1
    - google/auth v0.8 requires guzzlehttp/psr7 1.2.* -> satisfiable by guzzlehttp/psr7[1.2.0, 1.2.1, 1.2.2, 1.2.3].
    - Can only install one of: guzzlehttp/psr7[1.2.0, 1.3.1].
    - Can only install one of: guzzlehttp/psr7[1.2.1, 1.3.1].
    - Can only install one of: guzzlehttp/psr7[1.2.2, 1.3.1].
    - Can only install one of: guzzlehttp/psr7[1.2.3, 1.3.1].
    - Installation request for guzzlehttp/psr7 (locked at 1.3.1) -> satisfiable by guzzlehttp/psr7[1.3.1].


Installation failed, reverting ./composer.json to its original content.