Package check result: ERROR

Check: examples, Result: ERROR
  Running examples in ‘tidysq-Ex.R’ failed
  The error most likely occurred in:
  
  > base::assign(".ptime", proc.time(), pos = "CheckExEnv")
  > ### Name: export_sq
  > ### Title: Export sq objects into other formats
  > ### Aliases: export_sq
  > 
  > ### ** Examples
  > 
  > # DNA and amino acid sequences can be exported to most packages
  > sq_ami <- sq(c("MVVGL", "LAVPP"), alphabet = "ami_bsc")
  > export_sq(sq_ami, "ape::AAbin")
  Error in export_sq.sq_ami_bsc(sq_ami, "ape::AAbin") : 
    Assertion on '"ape"' failed: you need to install 'ape' package.
  Calls: export_sq ... export_sq.sq_ami_bsc -> assert_package_installed -> <Anonymous> -> mstop
  Execution halted