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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 collate(self, merge_type=None, drop=[], drop_constant=False):
 """Collate allows reordering nested containers Collation allows collapsing nested mapping types by merging their dimensions. In simple terms in merges nested containers into a single merged type. In the simple case a HoloMap containing other HoloMaps can easily be joined in this way. However collation is particularly useful when the objects being joined are deeply nested, e.g. you want to join multiple Layouts recorded at different times, collation will return one Layout containing HoloMaps indexed by Time. Changing the merge_type will allow merging the outer Dimension into any other UniformNdMapping type. Args: merge_type: Type of the object to merge with drop: List of dimensions to drop drop_constant: Drop constant dimensions automatically Returns: Collated Layout or HoloMap """

        from .element import Collator
        merge_type=merge_type if merge_type else self.__class__
        return Collator(self, merge_type=merge_type, drop=drop,
                        drop_constant=drop_constant)()