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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 delete(self, config_file=None):
 """Deletes the credentials file specified in `config_file`. If no file is specified, it deletes the default user credential file. Args: config_file (str):
 Path to configuration file. Defaults to delete the user default location if `None`. .. Tip:: To see if there is a default user credential file stored, do the following:: Credentials(username=eschbacher, key=abcdefg, base_url=https://eschbacher.carto.com/) """

        path_to_remove = config_file or _DEFAULT_PATH
        try:
            os.remove(path_to_remove)
            print('Credentials at {} successfully removed.'.format(
                path_to_remove))
        except OSError as err:
            warnings.warn('No credential file found at {}.'.format(
                path_to_remove))