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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 _controller_name(self, objtype):
 """Determines the controller name for the object's type Args: objtype (str):
 The object type Returns: A string with the controller name """

        # would be better to use inflect.pluralize here, but would add a dependency
        if objtype.endswith('y'):
            return objtype[:-1] + 'ies'

        if objtype[-1] in 'sx' or objtype[-2:] in ['sh', 'ch']:
            return objtype + 'es'

        if objtype.endswith('an'):
            return objtype[:-2] + 'en'

        return objtype + 's'