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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 _fetchAzureAccountKey(accountName):
 """ Find the account key for a given Azure storage account. The account key is taken from the AZURE_ACCOUNT_KEY_<account> environment variable if it exists, then from plain AZURE_ACCOUNT_KEY, and then from looking in the file ~/.toilAzureCredentials. That file has format: [AzureStorageCredentials] accountName1=ACCOUNTKEY1== accountName2=ACCOUNTKEY2== """

    try:
        return os.environ['AZURE_ACCOUNT_KEY_' + accountName]
    except KeyError:
        try:
            return os.environ['AZURE_ACCOUNT_KEY']
        except KeyError:
            configParser = RawConfigParser()
            configParser.read(os.path.expanduser(credential_file_path))
            try:
                return configParser.get('AzureStorageCredentials', accountName)
            except NoOptionError:
                raise RuntimeError("No account key found for '%s', please provide it in '%s'" %
                                   (accountName, credential_file_path))