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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 default_select(identifier, all_entry_points):
 # pylint: disable=inconsistent-return-statements """ Raise an exception when we have ambiguous entry points. """


    if len(all_entry_points) == 0:
        raise PluginMissingError(identifier)

    elif len(all_entry_points) == 1:
        return all_entry_points[0]

    elif len(all_entry_points) > 1:
        raise AmbiguousPluginError(all_entry_points)