Add a BTC currency to Paid Memberships Pro

pmpro_btc_currency_format.php

/**
 * Add a BTC currency to Paid Memberships Pro
 * Add this code into a custom plugin. https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */
function pmpro_btc_currency_format( $pmpro_currencies ) {
	$pmpro_currencies['BTC'] = array(
		'name' => __( 'Bitcoin', 'paid-memberships-pro' ),
		'decimals' => '8',
		'thousands_separator' => '',
		'decimal_separator' => '.',
		'symbol' => 'BTC',
		'position' => 'left',
	);
	return $pmpro_currencies;
}
add_filter( 'pmpro_currencies', 'pmpro_btc_currency_format' );