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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 filename(self):
 """ Build and return a filename from the various components. """

        if self.buildver:
            buildver = '-' + self.buildver
        else:
            buildver = ''
        pyver = '.'.join(self.pyver)
        abi = '.'.join(self.abi)
        arch = '.'.join(self.arch)
        # replace - with _ as a local version separator
        version = self.version.replace('-', '_')
        return '%s-%s%s-%s-%s-%s.whl' % (self.name, version, buildver,
                                         pyver, abi, arch)