Build Failure on Ubuntu 20.04.6 LTS (/bin/sh: 1: Syntax error: "(" unexpected)

[A4EVA]

Hello Everyone. I'm trying to build the project but It fails and I do not know why. I'm using the master branch and I downloaded the xtensa-lx106-elf-20160330.tgx and esp_iot_sdk_v2.1.0.tgx as reported in the travis.yml file. I then created a older called esp8266 and inside this folder I have the esp-link directory, esp_iot_sdk_v2.1.0 and the xtensa-lx106-elf directories. I edited the makefile since xtensa-lx106-elf is not in the esp-open-sdk folder. The project starts to build but then this error pops up:

/bin/sh: 1: Syntax error: "(" unexpected make: *** [Makefile:380: firmware/user1.bin] Error 2

Do I need to edit some other file to have a successful build ? Thanks a lot

[rootmax84]

@A4EVA try

sudo apt install python-is-python2