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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 v(self, version, max_version=None, **kwargs):
 """ Returns either a single requirement version or a requirement version range depending on whether two arguments are supplied or one Parameters version : str | Version Either a version of the requirement, or the first version in a range of acceptable versions """

        if not isinstance(version, Version):
            version = self.version_cls(self, version, **kwargs)
        # Return a version range instead of version
        if max_version is not None:
            if not isinstance(max_version, Version):
                max_version = self.version_cls(self, max_version, **kwargs)
            version = VersionRange(version, max_version)
        return version