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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 _libname(self):
 """Return platform-specific modelf90 shared library name."""

        prefix = 'lib'
        suffix = '.so'
        if platform.system() == 'Darwin':
            suffix = '.dylib'
        if platform.system() == 'Windows':
            prefix = ''
            suffix = '.dll'
        return prefix + self.engine + suffix