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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def whichall(command, path=None, verbose=0, exts=None):
 """Return a list of full paths to all matches of the given command on the path. "command" is a the name of the executable to search for. "path" is an optional alternate path list to search. The default it to use the PATH environment variable. "verbose", if true, will cause a 2-tuple to be returned for each match. The second element is a textual description of where the match was found. "exts" optionally allows one to specify a list of extensions to use instead of the standard list for this system. This can effectively be used as an optimization to, for example, avoid stat's of "foo.vbs" when searching for "foo" and you know it is not a VisualBasic script but ".vbs" is on PATHEXT. This option is only supported on Windows. """

    return list( whichgen(command, path, verbose, exts) )