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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 import_module(module_name):
 """ Given a dotted Python path, imports & returns the module. If not found, raises ``UnknownModuleError``. Ex:: mod = import_module('random') :param module_name: The dotted Python path :type module_name: string :returns: module """

    try:
        return importlib.import_module(module_name)
    except ImportError as err:
        raise UnknownModuleError(str(err))