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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 _is_custom_qs_manager(funcdef):
 """Checks if a function definition is a queryset manager created with the @queryset_manager decorator."""


    decors = getattr(funcdef, 'decorators', None)
    if decors:
        for dec in decors.get_children():
            try:
                if dec.name == 'queryset_manager':  # pragma no branch
                    return True
            except AttributeError:
                continue

    return False