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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 check_geom(c1, a1, c2, a2, tol=_DEF.XYZ_COORD_MATCH_TOL):
 """ Check for consistency of two geometries and atom symbol lists Cartesian coordinates are considered consistent with the input coords if each component matches to within `tol`. If coords or atoms vectors are passed that are of mismatched lengths, a |False| value is returned. Both coords vectors must be three times the length of the atoms vectors or a :exc:`~exceptions.ValueError` is raised. Parameters c1 length-3N |npfloat_| -- Vector of first set of stacked 'lab-frame' Cartesian coordinates a1 length-N |str| or |int| -- Vector of first set of atom symbols or atomic numbers c2 length-3N |npfloat_| -- Vector of second set of stacked 'lab-frame' Cartesian coordinates a2 length-N |str| or |int| -- Vector of second set of atom symbols or atomic numbers tol |float|, optional -- Tolerance for acceptable deviation of each geometry coordinate from that in the reference instance to still be considered matching. Default value is specified by :attr:`opan.const.DEF.XYZ_COORD_MATCH_TOL`) Returns ------- match |bool| -- Whether input coords and atoms match (|True|) or not (|False|) fail_type :class:`~opan.const.EnumCheckGeomMismatch` or |None| -- Type of check failure If `match` == |True|: Returns as |None| If `match` == |False|: An :class:`~opan.const.EnumCheckGeomMismatch` value indicating the reason for the failed match: :attr:`~opan.const.EnumCheckGeomMismatch.DIMENSION` -- Mismatch in geometry size (number of atoms) :attr:`~opan.const.EnumCheckGeomMismatch.COORDS` -- Mismatch in one or more coordinates :attr:`~opan.const.EnumCheckGeomMismatch.ATOMS` -- Mismatch in one or more atoms fail_loc length-3N |bool| or length-N |bool| or |None| -- Mismatched elements If `match` == |True|: Returns as |None| If `match` == |False|: For "array-level" problems such as a dimension mismatch, a |None| value is returned. For "element-level" problems, a vector is returned indicating positions of mismatch in either `coords` or `atoms`, depending on the value of `fail_type`. |True| elements indicate **MATCHING** values |False| elements mark **MISMATCHES** Raises ------ ~exceptions.ValueError If a pair of coords & atoms array lengths is inconsistent: .. code-block:: python if len(c1) != 3 * len(a1) or len(c2) != 3 * len(a2):
 """


    # Import(s)
    from ..const import atom_num
    import numpy as np
    from ..const import EnumCheckGeomMismatch as ECGM

    # Initialize return value to success condition
    match = True

    #** Check coords for suitable shape. Assume 1-D np.arrays.
    if not len(c1.shape) == 1:
        # Cannot coerce to vector; complain.
        raise ValueError(("'c1' is not a vector."))
    ## end if
    if not len(c2.shape) == 1:
        # Cannot coerce to vector; complain.
        raise ValueError(("'c2' is not a vector."))
    ## end if

    #** Check atoms for suitable shape. Assume lists of strings, so
    # convert to np.array to check.
    if not len(a1.shape) == 1:
        # Not a vector; complain
        raise ValueError(("'a1' is not a simple list."))
    ## end if
    if not len(a2.shape) == 1:
        # Not a vector; complain.
        raise ValueError(("'a2' is not a simple list."))
    ## end if

    #** Confirm proper lengths of coords vs atoms
    if not c1.shape[0] == 3 * a1.shape[0]:
        raise ValueError("len(c1) != 3*len(a1)")
    ## end if
    if not c2.shape[0] == 3 * a2.shape[0]:
        raise ValueError("len(c2) != 3*len(a2)")
    ## end if

    #** Confirm matching lengths of coords and atoms w/corresponding
    #  objects among the two geometries
    if not c1.shape[0] == c2.shape[0]:
        match = False
        fail_type = ECGM.DIMENSION
        return match, fail_type, None
    ## end if

    #** Element-wise check for geometry match to within 'tol'
    fail_loc = np.less_equal(np.abs(np.subtract(c1,c2)), tol)
    if sum(fail_loc) != c2.shape[0]:
        # Count of matching coordinates should equal the number of
        #  coordinates. If not, complain with 'coord_mismatch' fail type.
        match = False
        fail_type = ECGM.COORDS
        return match, fail_type, fail_loc
    ## end if

    #** Element-wise check for atoms match. Quietly convert both input and
    #  instance atom arrays to atom_nums to allow np.equals comparison.
    if np.issubdtype(a1.dtype, np.dtype('str')):
        # Presume atomic symbol data and attempt conversion
        a1 = np.array([atom_num[e] for e in a1])
    ## end if
    if np.issubdtype(a2.dtype, np.dtype('str')):
        # Presume atomic symbol data and attempt conversion
        a2 = np.array([atom_num[e] for e in a2])
    ## end if
    fail_loc = np.equal(a1, a2)

    #** Perform the test to ensure all atoms match.
    if sum(fail_loc) != a2.shape[0]:
        # Count of matching atoms should equal number of atoms. If not,
        #  complain with the 'atom_mismatch' fail type.
        match = False
        fail_type = ECGM.ATOMS
        return match, fail_type, fail_loc

    #** If reached here, all tests passed; return success.
    return match, None, None