| 
  | is_valid_pv_file(file_name)
   |  |  Returns bool indicating if the file appears to be a valid PV file. This function with throw an exception is the file is not a valid 
  Maestro structure file. The checks for this are simple, and may not be conclusive. The test is
  content, and not file-extension based, since there are valid PV or EPV 
  files that lack any indication that they are PV files in the file 
  extension. If you need to check the extension as well see 
  fileutils.is_poseviewer_file. A PV file has exactly one structure with a true value for 
  b_glide_receptor. An EPV file has one or more structures with a true value for 
  b_glide_receptor at the beginning of the file. Single-receptor EPV files 
  are therefore considered PV files, but not EPV files with two or more 
  receptors. 
    Parameters:
        file_name(str) - path to the structure fileReturns: boolbool indicating if the file appears to be a valid PV file |