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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def generate(env):
 """Add Builders and construction variables for Forte to an Environment."""

    link.generate(env)
    
    env['SHLINKFLAGS'] = SCons.Util.CLVar('$LINKFLAGS -G')

    env['RPATHPREFIX'] = '-R'
    env['RPATHSUFFIX'] = ''
    env['_RPATH'] = '${_concat(RPATHPREFIX, RPATH, RPATHSUFFIX, __env__)}'

    # Support for versioned libraries
    link._setup_versioned_lib_variables(env, tool = 'sunlink', use_soname = True) 
    env['LINKCALLBACKS'] = link._versioned_lib_callbacks()