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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 compaq visual fortran to an Environment."""


    fortran.generate(env)

    env['FORTRAN']        = 'f90'
    env['FORTRANCOM']     = '$FORTRAN $FORTRANFLAGS $_FORTRANMODFLAG $_FORTRANINCFLAGS /compile_only ${SOURCES.windows} /object:${TARGET.windows}'
    env['FORTRANPPCOM']   = '$FORTRAN $FORTRANFLAGS $CPPFLAGS $_CPPDEFFLAGS $_FORTRANMODFLAG $_FORTRANINCFLAGS /compile_only ${SOURCES.windows} /object:${TARGET.windows}'
    env['SHFORTRANCOM']   = '$SHFORTRAN $SHFORTRANFLAGS $_FORTRANMODFLAG $_FORTRANINCFLAGS /compile_only ${SOURCES.windows} /object:${TARGET.windows}'
    env['SHFORTRANPPCOM'] = '$SHFORTRAN $SHFORTRANFLAGS $CPPFLAGS $_CPPDEFFLAGS $_FORTRANMODFLAG $_FORTRANINCFLAGS /compile_only ${SOURCES.windows} /object:${TARGET.windows}'
    env['OBJSUFFIX']      = '.obj'
    env['FORTRANMODDIR'] = '${TARGET.dir}'
    env['FORTRANMODDIRPREFIX'] = '/module:'
    env['FORTRANMODDIRSUFFIX'] = ''