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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 build_api_url(project, method, base_url):
 """Construct the URL for a particular API call. This method is used internally to come up with the URL to use when making RPCs to the Cloud Datastore API. :type project: str :param project: The project to connect to. This is usually your project name in the cloud console. :type method: str :param method: The API method to call (e.g. 'runQuery', 'lookup'). :type base_url: str :param base_url: The base URL where the API lives. :rtype: str :returns: The API URL created. """

    return API_URL_TEMPLATE.format(
        api_base=base_url, api_version=API_VERSION, project=project, method=method
    )