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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 complain(distribution_name):
 """Issue a warning if `distribution_name` is installed. In a future release, this method will be updated to raise ImportError rather than just send a warning. Args: distribution_name (str):
 The name of the obsolete distribution. """

    try:
        pkg_resources.get_distribution(distribution_name)
        warnings.warn(
            "The {pkg} distribution is now obsolete. "
            "Please `pip uninstall {pkg}`. "
            "In the future, this warning will become an ImportError.".format(
                pkg=distribution_name
            ),
            DeprecationWarning,
        )
    except pkg_resources.DistributionNotFound:
        pass