Reduce redundant code

[TTz0601]

Reduce redundant code
Improve readability

[mr-avocado]

Dear contributor,
Avocado is currently under sprint #103, which is due to release an LTS (Long Term Stability) release.
Please avoid merging changes that do not fall into these categories:

• Bug fixes
• Usability Improvements
• Documentation updates

As for the Avocado utility modules (“avocado.utils”) it is OK to introduce new functionality,
but changes to the existing APIs (including interface and behavior) should be avoided.
These kind of changes should wait until sprint #104.

[richtja]

Hello @TTz0601, I appreciate your effort in implementing these changes. It LGTM.

The only thing that needs attention is the signature. In the "git log" records, the author is displayed as zuohanxu <zuohanxu@uniontech.com>, while the commit message carries the signature TTz0601 <1375888477@qq.com>. It seems that there's a discrepancy in the signatures used between your system settings and the commit messages. Could you please align these signatures for consistency? Thank you for your cooperation.