سلام 
کد رو که میزنم این پیغام رو میده
Reading package lists... Done 
Building dependency tree        
Reading state information... Done 
Package libc-dev is not available, but is referred to by another package. 
This may mean that the package is missing, has been obsoleted, or 
is only available from another source 
E: Package libc-dev has no installation candidate
چکار کنم؟؟؟!!!!!!! 
 
 
 
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