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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 gfortran to an Environment."""

    fortran.generate(env)

    for dialect in ['F77', 'F90', 'FORTRAN', 'F95', 'F03', 'F08']:
        env['%s' % dialect] = 'gfortran'
        env['SH%s' % dialect] = '$%s' % dialect
        if env['PLATFORM'] in ['cygwin', 'win32']:
            env['SH%sFLAGS' % dialect] = SCons.Util.CLVar('$%sFLAGS' % dialect)
        else:
            env['SH%sFLAGS' % dialect] = SCons.Util.CLVar('$%sFLAGS -fPIC' % dialect)

        env['INC%sPREFIX' % dialect] = "-I"
        env['INC%sSUFFIX' % dialect] = ""