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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 _get(function, return_format=None):
 """Get and return data from the API. :returns: A str, list, or dict, depending on the input values and API data. """

    if return_format:
        return requests.get(''.join([__BASE_URL, function, return_format])).text
    return requests.get(''.join([__BASE_URL, function, JSON])).json()