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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 hash_for_datasource(data_source):
 """Given a data_source, return its hash. :param data_source: The data_source name from a layer. :type data_source: str :returns: An md5 hash for the data source name. :rtype: str """

        import hashlib
        hash_value = hashlib.md5()
        hash_value.update(data_source.encode('utf-8'))
        hash_value = hash_value.hexdigest()
        return hash_value