Whoever bargains, contracts, or agrees, or attempts to bargain, contract, or agree with another that such other shall not bid upon or purchase any parcel of lands of the United States offered at public sale; or Whoever, by intimidation, combination, or unfair management, hinders, prevents, or attempts to hinder or prevent, any person from bidding upon or purchasing any tract of land so offered for sale - Shall be fined not more than $1,000 or imprisoned not more than one year, or both.