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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 can(ability, add_headers=None):
 """Test whether an ability is allowed."""

    client = ClientMixin(api_key=None)
    try:
        client.request('GET', endpoint='abilities/%s' % ability,
                       add_headers=add_headers)
        return True
    except Exception:
        pass
    return False