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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 has_shell_command(self, command):
 """Checks to see if a given check command exists on the device. Args: command: A string that is the name of the command to check. Returns: A boolean that is True if the command exists and False otherwise. """

        try:
            output = self.shell(['command', '-v',
                                 command]).decode('utf-8').strip()
            return command in output
        except AdbError:
            # If the command doesn't exist, then 'command -v' can return
            # an exit code > 1.
            return False