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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 case_sensitive_name(self, package_name):
 """ Return case-sensitive package name given any-case package name @param project_name: PyPI project name @type project_name: string """

        if len(self.environment[package_name]):
            return self.environment[package_name][0].project_name