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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 concat(objs, axis=0, join='outer', join_axes=None, ignore_index=False, keys=None, levels=None, names=None, verify_integrity=False, sort=None, copy=True):
 """ Concatenate pandas objects along a particular axis with optional set logic along the other axes. Can also add a layer of hierarchical indexing on the concatenation axis, which may be useful if the labels are the same (or overlapping) on the passed axis number. Parameters objs : a sequence or mapping of Series, DataFrame, or Panel objects If a dict is passed, the sorted keys will be used as the `keys` argument, unless it is passed, in which case the values will be selected (see below). Any None objects will be dropped silently unless they are all None in which case a ValueError will be raised. axis : {0/'index', 1/'columns'}, default 0 The axis to concatenate along. join : {'inner', 'outer'}, default 'outer' How to handle indexes on other axis (or axes). join_axes : list of Index objects Specific indexes to use for the other n - 1 axes instead of performing inner/outer set logic. ignore_index : bool, default False If True, do not use the index values along the concatenation axis. The concatenating objects where the concatenation axis does not have meaningful indexing information. Note the index values on the other axes are still respected in the join. keys : sequence, default None If multiple levels passed, should contain tuples. Construct hierarchical index using the passed keys as the outermost level. levels : list of sequences, default None Specific levels (unique values) to use for constructing a MultiIndex. Otherwise they will be inferred from the keys. names : list, default None Names for the levels in the resulting hierarchical index. verify_integrity : bool, default False Check whether the new concatenated axis contains duplicates. This can be very expensive relative to the actual data concatenation. sort : bool, default None Sort non-concatenation axis if it is not already aligned when `join` is 'outer'. The current default of sorting is deprecated and will change to not-sorting in a future version of pandas. Explicitly pass ``sort=True`` to silence the warning and sort. Explicitly pass ``sort=False`` to silence the warning and not sort. This has no effect when ``join='inner'``, which already preserves the order of the non-concatenation axis. .. versionadded:: 0.23.0 copy : bool, default True If False, do not copy data unnecessarily. Returns ------- object, type of objs When concatenating all ``Series`` along the index (axis=0), a ``Series`` is returned. When ``objs`` contains at least one ``DataFrame``, a ``DataFrame`` is returned. When concatenating along the columns (axis=1), a ``DataFrame`` is returned. See Also -------- Series.append : Concatenate Series. DataFrame.append : Concatenate DataFrames. DataFrame.join : Join DataFrames using indexes. DataFrame.merge : Merge DataFrames by indexes or columns. Notes ----- The keys, levels, and names arguments are all optional. A walkthrough of how this method fits in with other tools for combining pandas objects can be found `here <http://pandas.pydata.org/pandas-docs/stable/merging.html>`__. Examples -------- Combine two ``Series``. 0 a 1 b 0 c 1 d dtype: object Clear the existing index and reset it in the result by setting the ``ignore_index`` option to ``True``. 0 a 1 b 2 c 3 d dtype: object Add a hierarchical index at the outermost level of the data with the ``keys`` option. s1 0 a 1 b s2 0 c 1 d dtype: object Label the index keys you create with the ``names`` option. Series name Row ID s1 0 a 1 b s2 0 c 1 d dtype: object Combine two ``DataFrame`` objects with identical columns. letter number 0 a 1 1 b 2 letter number 0 c 3 1 d 4 letter number 0 a 1 1 b 2 0 c 3 1 d 4 Combine ``DataFrame`` objects with overlapping columns and return everything. Columns outside the intersection will be filled with ``NaN`` values. letter number animal 0 c 3 cat 1 d 4 dog letter number animal 0 a 1 NaN 1 b 2 NaN 0 c 3 cat 1 d 4 dog Combine ``DataFrame`` objects with overlapping columns and return only those that are shared by passing ``inner`` to the ``join`` keyword argument. letter number 0 a 1 1 b 2 0 c 3 1 d 4 Combine ``DataFrame`` objects horizontally along the x axis by passing in ``axis=1``. letter number animal name 0 a 1 bird polly 1 b 2 monkey george Prevent the result from including duplicate index values with the ``verify_integrity`` option. 0 a 1 0 a 2 Traceback (most recent call last):
 ValueError: Indexes have overlapping values: ['a'] """

    op = _Concatenator(objs, axis=axis, join_axes=join_axes,
                       ignore_index=ignore_index, join=join,
                       keys=keys, levels=levels, names=names,
                       verify_integrity=verify_integrity,
                       copy=copy, sort=sort)
    return op.get_result()