input: Write a function to generate a Python dictionary that contains the count of the characters in a given string. The function should return a dictionary where the keys are the characters and the values are the counts of those characters. If the input string is empty, the function should return an empty dictionary.
  assert count_chars("Hello World")=={'H': 1, 'e': 1, 'l': 3, 'o': 2, ' ': 1, 'W': 1, 'r': 1, 'd': 1}
  assert count_chars("Python")=={'P': 1, 'y': 1, 't': 1, 'h': 1, 'o': 1, 'n': 1}
  assert count_chars("aabbcc")=={'a': 2, 'b': 2, 'c': 2}
  assert count_chars("")=={}
  assert count_chars("12345")=={'1': 1, '2': 1, '3': 1, '4': 1, '5': 1}
  assert count_chars("!@#$%")=={'!': 1, '@': 1, '#': 1, '$': 1, '%': 1}
output: def count_chars(s):
      if not s:
          return {}
      char_count = {}
      for char in s:
          if char in char_count:
              char_count[char] += 1
          else:
              char_count[char] = 1
      return char_count