Firmware infos:

 build date : Wed Sep  2 17:14:50 CST 2020
 build id : MRA58K
 build display id : MRA58K test-keys
 mediatek version release : alps-mp-m0.mp1-V2.39_magc6580.we.c.m_P32
 platform : MT6580
 product brand : welcome
 product device : A91
 product manufacturer : welcome
 product model : A91 
 os version : 6.0

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