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

    try:
        bld = env['BUILDERS']['Rpm']
    except KeyError:
        bld = RpmBuilder
        env['BUILDERS']['Rpm'] = bld

    env.SetDefault(RPM          = 'LC_ALL=C rpmbuild')
    env.SetDefault(RPMFLAGS     = SCons.Util.CLVar('-ta'))
    env.SetDefault(RPMCOM       = rpmAction)
    env.SetDefault(RPMSUFFIX    = '.rpm')