// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;


contract ReentrancyGuard {
  bool private _notEntered;

  function __ReentrancyGuard_init () internal {
    _notEntered = true;
  }

  /**
   * @dev Prevents a contract from calling itself, directly or indirectly.
   * Calling a `nonReentrant` function from another `nonReentrant`
   * function is not supported. It is possible to prevent this from happening
   * by making the `nonReentrant` function external, and make it call a
   * `private` function that does the actual work.
   */
  modifier nonReentrant() {
    // On the first call to nonReentrant, _notEntered will be true
    require(_notEntered, "ReentrancyGuard: reentrant call");

    // Any calls to nonReentrant after this point will fail
    _notEntered = false;

    _;

    // By storing the original value once again, a refund is triggered (see
    // https://eips.ethereum.org/EIPS/eip-2200)
    _notEntered = true;
  }
}