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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 _SnakeCaseToCamelCase(path_name):
 """Converts a path name from snake_case to camelCase."""

  result = []
  after_underscore = False
  for c in path_name:
    if c.isupper():
      raise Error('Fail to print FieldMask to Json string: Path name '
                  '{0} must not contain uppercase letters.'.format(path_name))
    if after_underscore:
      if c.islower():
        result.append(c.upper())
        after_underscore = False
      else:
        raise Error('Fail to print FieldMask to Json string: The '
                    'character after a "_" must be a lowercase letter '
                    'in path name {0}.'.format(path_name))
    elif c == '_':
      after_underscore = True
    else:
      result += c

  if after_underscore:
    raise Error('Fail to print FieldMask to Json string: Trailing "_" '
                'in path name {0}.'.format(path_name))
  return ''.join(result)