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var baseAssignValue = require('./_baseAssignValue'),    createAggregator = require('./_createAggregator');
/** Used for built-in method references. */var objectProto = Object.prototype;
/** Used to check objects for own properties. */var hasOwnProperty = objectProto.hasOwnProperty;
/** * Creates an object composed of keys generated from the results of running * each element of `collection` thru `iteratee`. The corresponding value of * each key is the number of times the key was returned by `iteratee`. The * iteratee is invoked with one argument: (value). * * @static * @memberOf _ * @since 0.5.0 * @category Collection * @param {Array|Object} collection The collection to iterate over. * @param {Function} [iteratee=_.identity] The iteratee to transform keys. * @returns {Object} Returns the composed aggregate object. * @example * * _.countBy([6.1, 4.2, 6.3], Math.floor); * // => { '4': 1, '6': 2 } * * // The `_.property` iteratee shorthand. * _.countBy(['one', 'two', 'three'], 'length'); * // => { '3': 2, '5': 1 } */var countBy = createAggregator(function(result, value, key) {  if (hasOwnProperty.call(result, key)) {    ++result[key];  } else {    baseAssignValue(result, key, 1);  }});
module.exports = countBy;